Post-merge post-merge fix (new error codes for fparser).

.bzrignore

@@ -386,6 +386,7 @@ libmysqld/opt_ft.cc
 libmysqld/opt_range.cc
 libmysqld/opt_sum.cc
 libmysqld/pack.c
+libmysqld/parse_file.cc
 libmysqld/password.c
 libmysqld/procedure.cc
 libmysqld/protocol.cc

BitKeeper/etc/logging_ok

@@ -161,6 +161,7 @@ tim@sand.box
 tim@threads.polyesthetic.msg
 tim@white.box
 tim@work.mysql.com
+timour@mysql.com
 tom@basil-firewall.home.com
 tomas@mc05.(none)
 tonu@hundin.mysql.fi

include/my_sys.h

@@ -121,6 +121,13 @@ extern int NEAR my_errno;		/* Last error in mysys */
 #define MY_ERRNO_EDOM		33
 #define MY_ERRNO_ERANGE		34
 
+	/* Bits for get_date timeflag */
+#define GETDATE_DATE_TIME	1
+#define GETDATE_SHORT_DATE	2
+#define GETDATE_HHMMSSTIME	4
+#define GETDATE_GMT		8
+#define GETDATE_FIXEDLENGTH	16
+
 	/* defines when allocating data */
 #ifdef SAFEMALLOC
 #define my_malloc(SZ,FLAG) _mymalloc((SZ), __FILE__, __LINE__, FLAG )

include/mysqld_error.h

@@ -349,4 +349,9 @@
 #define ER_SP_VARCOND_AFTER_CURSHNDLR 1330
 #define ER_SP_CURSOR_AFTER_HANDLER 1331
 #define ER_SP_CASE_NOT_FOUND 1332
-#define ER_ERROR_MESSAGES 333
+#define ER_FPARSER_TOO_BIG_FILE 1333
+#define ER_FPARSER_BAD_HEADER 1334
+#define ER_FPARSER_EOF_IN_COMMENT 1335
+#define ER_FPARSER_ERROR_IN_PARAMETER 1336
+#define ER_FPARSER_EOF_IN_UNKNOWN_PARAMETER 1337
+#define ER_ERROR_MESSAGES 338

libmysqld/Makefile.am

@@ -58,7 +58,8 @@ sqlsources = derror.cc field.cc field_conv.cc strfunc.cc filesort.cc \
 	sql_update.cc sql_yacc.cc table.cc thr_malloc.cc time.cc \
 	unireg.cc uniques.cc stacktrace.c sql_union.cc hash_filo.cc \
 	spatial.cc gstream.cc sql_help.cc protocol_cursor.cc \
-	sp_head.cc sp_pcontext.cc sp.cc sp_cache.cc sp_rcontext.cc
+	sp_head.cc sp_pcontext.cc sp.cc sp_cache.cc sp_rcontext.cc \
+	parse_file.cc
 
 libmysqld_int_a_SOURCES= $(libmysqld_sources) $(libmysqlsources) $(sqlsources)
 libmysqld_a_SOURCES=

mysql-test/r/distinct.result

@@ -388,8 +388,8 @@ SELECT DISTINCTROW email, shipcode FROM t1, t2 WHERE t1.infoID=t2.infoID;
 email	shipcode
 test1@testdomain.com	Z001
 test2@testdomain.com	Z001
-test3@testdomain.com	Z001
 test2@testdomain.com	R002
+test3@testdomain.com	Z001
 SELECT DISTINCTROW email FROM t1 ORDER BY dateentered DESC;
 email
 test1@testdomain.com

mysql-test/r/func_group.result

@@ -183,12 +183,12 @@ insert into t2 values('BBB', 20, 1.0);
 select t1.a1, t1.a2, t2.a1, t2.a2 from t1,t2;
 a1	a2	a1	a2
 10	aaa	AAA	10
-10	NULL	AAA	10
-10	bbb	AAA	10
-20	zzz	AAA	10
 10	aaa	BBB	20
+10	NULL	AAA	10
 10	NULL	BBB	20
+10	bbb	AAA	10
 10	bbb	BBB	20
+20	zzz	AAA	10
 20	zzz	BBB	20
 select max(t1.a1), max(t2.a1) from t1, t2 where t2.a2=9;
 max(t1.a1)	max(t2.a1)

mysql-test/r/greedy_optimizer.result

@@ -0,0 +1,657 @@
+drop table if exists t1,t2,t3,t4,t5,t6,t7;
+create table t1 (
+c11 integer,c12 integer,c13 integer,c14 integer,c15 integer,c16 integer,
+primary key (c11)
+);
+create table t2 (
+c21 integer,c22 integer,c23 integer,c24 integer,c25 integer,c26 integer,
+);
+create table t3 (
+c31 integer,c32 integer,c33 integer,c34 integer,c35 integer,c36 integer,
+primary key (c31)
+);
+create table t4 (
+c41 integer,c42 integer,c43 integer,c44 integer,c45 integer,c46 integer
+);
+create table t5 (
+c51 integer,c52 integer,c53 integer,c54 integer,c55 integer,c56 integer,
+primary key (c51)
+);
+create table t6 (
+c61 integer,c62 integer,c63 integer,c64 integer,c65 integer,c66 integer
+);
+create table t7 (
+c71 integer,c72 integer,c73 integer,c74 integer,c75 integer,c76 integer,
+primary key (c71)
+);
+insert into t1 values (1,2,3,4,5,6);
+insert into t1 values (2,2,3,4,5,6);
+insert into t1 values (3,2,3,4,5,6);
+insert into t2 values (1,2,3,4,5,6);
+insert into t2 values (2,2,3,4,5,6);
+insert into t2 values (3,2,3,4,5,6);
+insert into t2 values (4,2,3,4,5,6);
+insert into t2 values (5,2,3,4,5,6);
+insert into t2 values (6,2,3,4,5,6);
+insert into t3 values (1,2,3,4,5,6);
+insert into t3 values (2,2,3,4,5,6);
+insert into t3 values (3,2,3,4,5,6);
+insert into t3 values (4,2,3,4,5,6);
+insert into t3 values (5,2,3,4,5,6);
+insert into t3 values (6,2,3,4,5,6);
+insert into t3 values (7,2,3,4,5,6);
+insert into t3 values (8,2,3,4,5,6);
+insert into t3 values (9,2,3,4,5,6);
+insert into t4 values (1,2,3,4,5,6);
+insert into t4 values (2,2,3,4,5,6);
+insert into t4 values (3,2,3,4,5,6);
+insert into t4 values (4,2,3,4,5,6);
+insert into t4 values (5,2,3,4,5,6);
+insert into t4 values (6,2,3,4,5,6);
+insert into t4 values (7,2,3,4,5,6);
+insert into t4 values (8,2,3,4,5,6);
+insert into t4 values (9,2,3,4,5,6);
+insert into t4 values (10,2,3,4,5,6);
+insert into t4 values (11,2,3,4,5,6);
+insert into t4 values (12,2,3,4,5,6);
+insert into t5 values (1,2,3,4,5,6);
+insert into t5 values (2,2,3,4,5,6);
+insert into t5 values (3,2,3,4,5,6);
+insert into t5 values (4,2,3,4,5,6);
+insert into t5 values (5,2,3,4,5,6);
+insert into t5 values (6,2,3,4,5,6);
+insert into t5 values (7,2,3,4,5,6);
+insert into t5 values (8,2,3,4,5,6);
+insert into t5 values (9,2,3,4,5,6);
+insert into t5 values (10,2,3,4,5,6);
+insert into t5 values (11,2,3,4,5,6);
+insert into t5 values (12,2,3,4,5,6);
+insert into t5 values (13,2,3,4,5,6);
+insert into t5 values (14,2,3,4,5,6);
+insert into t5 values (15,2,3,4,5,6);
+insert into t6 values (1,2,3,4,5,6);
+insert into t6 values (2,2,3,4,5,6);
+insert into t6 values (3,2,3,4,5,6);
+insert into t6 values (4,2,3,4,5,6);
+insert into t6 values (5,2,3,4,5,6);
+insert into t6 values (6,2,3,4,5,6);
+insert into t6 values (7,2,3,4,5,6);
+insert into t6 values (8,2,3,4,5,6);
+insert into t6 values (9,2,3,4,5,6);
+insert into t6 values (10,2,3,4,5,6);
+insert into t6 values (11,2,3,4,5,6);
+insert into t6 values (12,2,3,4,5,6);
+insert into t6 values (13,2,3,4,5,6);
+insert into t6 values (14,2,3,4,5,6);
+insert into t6 values (15,2,3,4,5,6);
+insert into t6 values (16,2,3,4,5,6);
+insert into t6 values (17,2,3,4,5,6);
+insert into t6 values (18,2,3,4,5,6);
+insert into t7 values (1,2,3,4,5,6);
+insert into t7 values (2,2,3,4,5,6);
+insert into t7 values (3,2,3,4,5,6);
+insert into t7 values (4,2,3,4,5,6);
+insert into t7 values (5,2,3,4,5,6);
+insert into t7 values (6,2,3,4,5,6);
+insert into t7 values (7,2,3,4,5,6);
+insert into t7 values (8,2,3,4,5,6);
+insert into t7 values (9,2,3,4,5,6);
+insert into t7 values (10,2,3,4,5,6);
+insert into t7 values (11,2,3,4,5,6);
+insert into t7 values (12,2,3,4,5,6);
+insert into t7 values (13,2,3,4,5,6);
+insert into t7 values (14,2,3,4,5,6);
+insert into t7 values (15,2,3,4,5,6);
+insert into t7 values (16,2,3,4,5,6);
+insert into t7 values (17,2,3,4,5,6);
+insert into t7 values (18,2,3,4,5,6);
+insert into t7 values (19,2,3,4,5,6);
+insert into t7 values (20,2,3,4,5,6);
+insert into t7 values (21,2,3,4,5,6);
+select @@plan_search_depth;
+@@plan_search_depth
+62
+select @@heuristic;
+@@heuristic
+1
+set plan_search_depth=63;
+select @@plan_search_depth;
+@@plan_search_depth
+63
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+set heuristic=0;
+select @@heuristic;
+@@heuristic
+0
+set plan_search_depth=0;
+select @@plan_search_depth;
+@@plan_search_depth
+0
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	
+1	SIMPLE	t1	eq_ref	PRIMARY	PRIMARY	4	test.t2.c21	1	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	274.419727
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	
+1	SIMPLE	t1	eq_ref	PRIMARY	PRIMARY	4	test.t2.c21	1	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	274.419727
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t1	eq_ref	PRIMARY	PRIMARY	4	test.t2.c21	1	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	274.419727
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t1	eq_ref	PRIMARY	PRIMARY	4	test.t2.c21	1	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	274.419727
+set plan_search_depth=1;
+select @@plan_search_depth;
+@@plan_search_depth
+1
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+set plan_search_depth=62;
+select @@plan_search_depth;
+@@plan_search_depth
+62
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	
+1	SIMPLE	t1	eq_ref	PRIMARY	PRIMARY	4	test.t2.c21	1	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	274.419727
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	
+1	SIMPLE	t1	eq_ref	PRIMARY	PRIMARY	4	test.t2.c21	1	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	274.419727
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t1	eq_ref	PRIMARY	PRIMARY	4	test.t2.c21	1	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	274.419727
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t1	eq_ref	PRIMARY	PRIMARY	4	test.t2.c21	1	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	274.419727
+set heuristic=1;
+select @@heuristic;
+@@heuristic
+1
+set plan_search_depth=0;
+select @@plan_search_depth;
+@@plan_search_depth
+0
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+set plan_search_depth=1;
+select @@plan_search_depth;
+@@plan_search_depth
+1
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+set plan_search_depth=62;
+select @@plan_search_depth;
+@@plan_search_depth
+62
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t2.c22	1	
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t4.c42	1	
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t6.c62	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	821.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using index
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using index
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using index
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	PRIMARY	NULL	NULL	NULL	3	
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t3	eq_ref	PRIMARY	PRIMARY	4	test.t1.c12	1	Using where
+1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	12	Using where
+1	SIMPLE	t5	eq_ref	PRIMARY	PRIMARY	4	test.t1.c14	1	Using where
+1	SIMPLE	t6	ALL	NULL	NULL	NULL	NULL	18	Using where
+1	SIMPLE	t7	eq_ref	PRIMARY	PRIMARY	4	test.t1.c16	1	Using where
+show status like 'Last_query_cost';
+Variable_name	Value
+Last_query_cost	794.838037
+drop table t1,t2,t3,t4,t5,t6,t7;

mysql-test/r/select.result

@@ -1393,8 +1393,8 @@ companynr	companynr
 41	40
 explain select distinct t2.companynr,t4.companynr from t2,t4 where t2.companynr=t4.companynr+1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using temporary
+1	SIMPLE	t4	index	NULL	PRIMARY	1	NULL	12	Using index; Using temporary
-1	SIMPLE	t4	index	NULL	PRIMARY	1	NULL	12	Using where; Using index
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1199	Using where
 select t2.fld1,t2.companynr,fld3,period from t3,t2 where t2.fld1 = 38208 and t2.fld1=t3.t2nr and period = 1008 or t2.fld1 = 38008 and t2.fld1 =t3.t2nr and period = 1008;
 fld1	companynr	fld3	period
 038008	37	reporters	1008
@@ -2314,8 +2314,8 @@ left join t4 on id3 = id4 where id2 = 1 or id4 = 1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t3	system	NULL	NULL	NULL	NULL	0	const row not found
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	
-1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1	
+1	SIMPLE	t4	ALL	id4	NULL	NULL	NULL	1	
-1	SIMPLE	t4	ALL	id4	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1	Using where
 select * from t1 left join t2 on id1 = id2 left join t3 on id1 = id3
 left join t4 on id3 = id4 where id2 = 1 or id4 = 1;
 id1	id2	id3	id4	id44

mysql-test/r/subselect.result

@@ -1348,8 +1348,8 @@ a
 explain extended select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t2	index	NULL	a	5	NULL	4	Using where; Using index
-2	DEPENDENT SUBQUERY	t1	ref	a	a	5	func	1001	Using where; Using index
+2	DEPENDENT SUBQUERY	t3	index	a	a	5	NULL	3	Using index
-2	DEPENDENT SUBQUERY	t3	index	a	a	5	NULL	3	Using where; Using index
+2	DEPENDENT SUBQUERY	t1	ref	a	a	10	func,test.t3.a	1000	Using where; Using index
 Warnings:
 Note	1003	select high_priority test.t2.a AS `a` from test.t2 where <in_optimizer>(test.t2.a,<exists>(select 1 AS `Not_used` from test.t1 join test.t3 where ((test.t1.b = test.t3.a) and (<cache>(test.t2.a) = test.t1.a))))
 insert into t1 values (3,31);

mysql-test/t/greedy_optimizer.test

@@ -0,0 +1,313 @@
+#
+# A simple test of the greedy query optimization algorithm and the switches that
+# control the optimizationprocess.
+#
+
+#
+# Schema
+#
+--disable_warnings
+drop table if exists t1,t2,t3,t4,t5,t6,t7;
+--enable_warnings
+
+create table t1 (
+  c11 integer,c12 integer,c13 integer,c14 integer,c15 integer,c16 integer,
+  primary key (c11)
+);
+create table t2 (
+  c21 integer,c22 integer,c23 integer,c24 integer,c25 integer,c26 integer,
+);
+create table t3 (
+  c31 integer,c32 integer,c33 integer,c34 integer,c35 integer,c36 integer,
+  primary key (c31)
+);
+create table t4 (
+  c41 integer,c42 integer,c43 integer,c44 integer,c45 integer,c46 integer
+);
+create table t5 (
+  c51 integer,c52 integer,c53 integer,c54 integer,c55 integer,c56 integer,
+  primary key (c51)
+);
+create table t6 (
+  c61 integer,c62 integer,c63 integer,c64 integer,c65 integer,c66 integer
+);
+create table t7 (
+  c71 integer,c72 integer,c73 integer,c74 integer,c75 integer,c76 integer,
+  primary key (c71)
+);
+
+#
+# Data
+# cardinality(Ti) = cardinality(T(i-1)) + 3
+#
+insert into t1 values (1,2,3,4,5,6);
+insert into t1 values (2,2,3,4,5,6);
+insert into t1 values (3,2,3,4,5,6);
+
+insert into t2 values (1,2,3,4,5,6);
+insert into t2 values (2,2,3,4,5,6);
+insert into t2 values (3,2,3,4,5,6);
+insert into t2 values (4,2,3,4,5,6);
+insert into t2 values (5,2,3,4,5,6);
+insert into t2 values (6,2,3,4,5,6);
+
+insert into t3 values (1,2,3,4,5,6);
+insert into t3 values (2,2,3,4,5,6);
+insert into t3 values (3,2,3,4,5,6);
+insert into t3 values (4,2,3,4,5,6);
+insert into t3 values (5,2,3,4,5,6);
+insert into t3 values (6,2,3,4,5,6);
+insert into t3 values (7,2,3,4,5,6);
+insert into t3 values (8,2,3,4,5,6);
+insert into t3 values (9,2,3,4,5,6);
+
+insert into t4 values (1,2,3,4,5,6);
+insert into t4 values (2,2,3,4,5,6);
+insert into t4 values (3,2,3,4,5,6);
+insert into t4 values (4,2,3,4,5,6);
+insert into t4 values (5,2,3,4,5,6);
+insert into t4 values (6,2,3,4,5,6);
+insert into t4 values (7,2,3,4,5,6);
+insert into t4 values (8,2,3,4,5,6);
+insert into t4 values (9,2,3,4,5,6);
+insert into t4 values (10,2,3,4,5,6);
+insert into t4 values (11,2,3,4,5,6);
+insert into t4 values (12,2,3,4,5,6);
+
+insert into t5 values (1,2,3,4,5,6);
+insert into t5 values (2,2,3,4,5,6);
+insert into t5 values (3,2,3,4,5,6);
+insert into t5 values (4,2,3,4,5,6);
+insert into t5 values (5,2,3,4,5,6);
+insert into t5 values (6,2,3,4,5,6);
+insert into t5 values (7,2,3,4,5,6);
+insert into t5 values (8,2,3,4,5,6);
+insert into t5 values (9,2,3,4,5,6);
+insert into t5 values (10,2,3,4,5,6);
+insert into t5 values (11,2,3,4,5,6);
+insert into t5 values (12,2,3,4,5,6);
+insert into t5 values (13,2,3,4,5,6);
+insert into t5 values (14,2,3,4,5,6);
+insert into t5 values (15,2,3,4,5,6);
+
+insert into t6 values (1,2,3,4,5,6);
+insert into t6 values (2,2,3,4,5,6);
+insert into t6 values (3,2,3,4,5,6);
+insert into t6 values (4,2,3,4,5,6);
+insert into t6 values (5,2,3,4,5,6);
+insert into t6 values (6,2,3,4,5,6);
+insert into t6 values (7,2,3,4,5,6);
+insert into t6 values (8,2,3,4,5,6);
+insert into t6 values (9,2,3,4,5,6);
+insert into t6 values (10,2,3,4,5,6);
+insert into t6 values (11,2,3,4,5,6);
+insert into t6 values (12,2,3,4,5,6);
+insert into t6 values (13,2,3,4,5,6);
+insert into t6 values (14,2,3,4,5,6);
+insert into t6 values (15,2,3,4,5,6);
+insert into t6 values (16,2,3,4,5,6);
+insert into t6 values (17,2,3,4,5,6);
+insert into t6 values (18,2,3,4,5,6);
+
+insert into t7 values (1,2,3,4,5,6);
+insert into t7 values (2,2,3,4,5,6);
+insert into t7 values (3,2,3,4,5,6);
+insert into t7 values (4,2,3,4,5,6);
+insert into t7 values (5,2,3,4,5,6);
+insert into t7 values (6,2,3,4,5,6);
+insert into t7 values (7,2,3,4,5,6);
+insert into t7 values (8,2,3,4,5,6);
+insert into t7 values (9,2,3,4,5,6);
+insert into t7 values (10,2,3,4,5,6);
+insert into t7 values (11,2,3,4,5,6);
+insert into t7 values (12,2,3,4,5,6);
+insert into t7 values (13,2,3,4,5,6);
+insert into t7 values (14,2,3,4,5,6);
+insert into t7 values (15,2,3,4,5,6);
+insert into t7 values (16,2,3,4,5,6);
+insert into t7 values (17,2,3,4,5,6);
+insert into t7 values (18,2,3,4,5,6);
+insert into t7 values (19,2,3,4,5,6);
+insert into t7 values (20,2,3,4,5,6);
+insert into t7 values (21,2,3,4,5,6);
+
+#
+# The actual test begins here
+#
+
+# Check the default values for the optimizer paramters
+
+select @@plan_search_depth;
+select @@heuristic;
+
+-- This value swithes back to the old implementation of 'find_best()'
+-- set plan_search_depth=63; - old (independent of the heuristic)
+--
+-- These are the values for the parameters that control the greedy optimizer
+-- (total 6 combinations - 3 for plan_search_depth, 2 for heuristic):
+--
+-- set plan_search_depth=0;  - automatic
+-- set plan_search_depth=1;  - min
+-- set plan_search_depth=62; - max (default)
+--
+-- set heuristic=0 - exhaustive;
+-- set heuristic=1 - heuristic; -- default
+
+
+#
+# Compile several queries with all combinations of the query
+# optimizer parameters. Each test query has two variants, where
+# in the second variant the tables in the FROM clause are in
+# inverse order to the tables in the first variant.
+# Due to pre-sorting of tables before compilation, there should
+# be no difference in the plans for each two such query variants.
+#
+
+# First, for reference compile the test queries with the 'old' optimization
+# procedure 'find_best'. Notice that 'find_best' does not depend on the
+# choice of heuristic.
+
+set plan_search_depth=63;
+select @@plan_search_depth;
+
+-- 6-table join, chain
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, star
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, clique
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+
+
+# Test the new optimization procedures
+
+set heuristic=0;
+select @@heuristic;
+
+set plan_search_depth=0;
+select @@plan_search_depth;
+
+-- 6-table join, chain
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, star
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, clique
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+
+set plan_search_depth=1;
+select @@plan_search_depth;
+
+-- 6-table join, chain
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, star
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, clique
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+
+set plan_search_depth=62;
+select @@plan_search_depth;
+
+-- 6-table join, chain
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, star
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, clique
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+
+
+set heuristic=1;
+select @@heuristic;
+
+set plan_search_depth=0;
+select @@plan_search_depth;
+
+-- 6-table join, chain
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, star
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, clique
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+
+set plan_search_depth=1;
+select @@plan_search_depth;
+
+-- 6-table join, chain
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, star
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, clique
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+
+set plan_search_depth=62;
+select @@plan_search_depth;
+
+-- 6-table join, chain
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c12 = t2.c21 and t2.c22 = t3.c31 and t3.c32 = t4.c41 and t4.c42 = t5.c51 and t5.c52 = t6.c61 and t6.c62 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, star
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71;
+show status like 'Last_query_cost';
+-- 6-table join, clique
+explain select t1.c11 from t1, t2, t3, t4, t5, t6, t7 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+explain select t1.c11 from t7, t6, t5, t4, t3, t2, t1 where t1.c11 = t2.c21 and t1.c12 = t3.c31 and t1.c13 = t4.c41 and t1.c14 = t5.c51 and t1.c15 = t6.c61 and t1.c16 = t7.c71 and t2.c22 = t3.c32 and t2.c23 = t4.c42 and t2.c24 = t5.c52 and t2.c25 = t6.c62 and t2.c26 = t7.c72 and t3.c33 = t4.c43 and t3.c34 = t5.c53 and t3.c35 = t6.c63 and t3.c36 = t7.c73 and t4.c42 = t5.c54 and t4.c43 = t6.c64 and t4.c44 = t7.c74 and t5.c52 = t6.c65 and t5.c53 = t7.c75 and t6.c62 = t7.c76;
+show status like 'Last_query_cost';
+
+drop table t1,t2,t3,t4,t5,t6,t7;

mysys/mf_getdate.c

@@ -19,11 +19,20 @@
 #include "mysys_priv.h"
 #include <m_string.h>
 
-	/*
+/*
-	  If flag & 1 Return date and time
+  get date as string
-	  If flag & 2 Return short date format YYMMDD
+
-	  if flag & 4 Return time in HHMMDD format.
+  SYNOPSIS
-	  */
+    get_date()
+    to   - string where date will be written
+    flag - format of date:
+	  If flag & GETDATE_TIME	Return date and time
+	  If flag & GETDATE_SHORT_DATE	Return short date format YYMMDD
+	  If flag & GETDATE_HHMMSSTIME	Return time in HHMMDD format.
+	  If flag & GETDATE_GMT		Date/time in GMT
+	  If flag & GETDATE_FIXEDLENGTH	Return fixed length date/time
+    date - for conversion
+*/
 
 
 void get_date(register my_string to, int flag, time_t date)
@@ -36,27 +45,36 @@ void get_date(register my_string to, int flag, time_t date)
 
    skr=date ? (time_t) date : time((time_t*) 0);
 #if defined(HAVE_LOCALTIME_R) && defined(_REENTRANT)
-   localtime_r(&skr,&tm_tmp);
+   if (flag & GETDATE_GMT)
+     localtime_r(&skr,&tm_tmp);
+   else
+     gmtime_r(&skr,&tm_tmp);
    start_time= &tm_tmp;
 #else
-   start_time=localtime(&skr);
+   if (flag & GETDATE_GMT)
+     start_time= localtime(&skr);
+   else
+     gmtime(&skr,&tm_tmp);
 #endif
-   if (flag & 2)
+   if (flag & GETDATE_SHORT_DATE)
      sprintf(to,"%02d%02d%02d",
 	     start_time->tm_year % 100,
 	     start_time->tm_mon+1,
 	     start_time->tm_mday);
    else
-     sprintf(to,"%d-%02d-%02d",
+     sprintf(to, ((flag & GETDATE_FIXEDLENGTH) ?
+		  "%4d-%02d-%02d" : "%d-%02d-%02d"),
 	     start_time->tm_year+1900,
 	     start_time->tm_mon+1,
 	     start_time->tm_mday);
-   if (flag & 1)
+   if (flag & GETDATE_DATE_TIME)
-     sprintf(strend(to)," %2d:%02d:%02d",
+     sprintf(strend(to),
+	     ((flag & GETDATE_FIXEDLENGTH) ?
+	      " %02d:%02d:%02d" : " %2d:%02d:%02d"),
 	     start_time->tm_hour,
 	     start_time->tm_min,
 	     start_time->tm_sec);
-   else if (flag & 4)
+   else if (flag & GETDATE_HHMMSSTIME)
      sprintf(strend(to),"%02d%02d%02d",
 	     start_time->tm_hour,
 	     start_time->tm_min,

sql/Makefile.am

@@ -59,7 +59,8 @@ noinst_HEADERS =	item.h item_func.h item_sum.h item_cmpfunc.h \
 			stacktrace.h sql_sort.h sql_cache.h set_var.h \
 			spatial.h gstream.h client_settings.h \
 			examples/ha_example.h \
-			sp_head.h sp_pcontext.h sp_rcontext.h sp.h sp_cache.h
+			sp_head.h sp_pcontext.h sp_rcontext.h sp.h sp_cache.h \
+			parse_file.h			
 mysqld_SOURCES =	sql_lex.cc sql_handler.cc \
 			item.cc item_sum.cc item_buff.cc item_func.cc \
 			item_cmpfunc.cc item_strfunc.cc item_timefunc.cc \
@@ -91,7 +92,7 @@ mysqld_SOURCES =	sql_lex.cc sql_handler.cc \
 			gstream.cc spatial.cc sql_help.cc protocol_cursor.cc \
 			examples/ha_example.cc \
 			sp_head.cc sp_pcontext.cc  sp_rcontext.cc sp.cc \
-			sp_cache.cc
+			sp_cache.cc parse_file.cc
 gen_lex_hash_SOURCES =	gen_lex_hash.cc
 gen_lex_hash_LDADD =	$(LDADD) $(CXXLDFLAGS)
 

sql/mysql_priv.h

@@ -375,6 +375,7 @@ inline THD *_current_thd(void)
 #include "sql_list.h"
 #include "sql_map.h"
 #include "handler.h"
+#include "parse_file.h"
 #include "table.h"
 #include "field.h"				/* Field definitions */
 #include "protocol.h"
@@ -787,6 +788,8 @@ extern "C" pthread_handler_decl(handle_manager, arg);
 void print_where(COND *cond,const char *info);
 void print_cached_tables(void);
 void TEST_filesort(SORT_FIELD *sortorder,uint s_length);
+void print_plan(JOIN* join, double read_time, double record_count,
+                uint idx, const char *info);
 #endif
 void mysql_print_status(THD *thd);
 /* key.cc */
@@ -854,6 +857,7 @@ extern char language[LIBLEN],reg_ext[FN_EXTLEN];
 extern char glob_hostname[FN_REFLEN], mysql_home[FN_REFLEN];
 extern char pidfile_name[FN_REFLEN], time_zone[30], *opt_init_file;
 extern char log_error_file[FN_REFLEN];
+extern double last_query_cost;
 extern double log_10[32];
 extern ulonglong log_10_int[20];
 extern ulonglong keybuff_size;

sql/mysqld.cc

@@ -312,6 +312,7 @@ ulong expire_logs_days = 0;
 ulong rpl_recovery_rank=0;
 ulong my_bind_addr;			/* the address we bind to */
 volatile ulong cached_thread_count= 0;
+double last_query_cost= -1; /* -1 denotes that no query was compiled yet */
 
 double log_10[32];			/* 10 potences */
 ulonglong log_10_int[20]=
@@ -3775,7 +3776,9 @@ enum options_mysqld
   OPT_DATE_FORMAT,
   OPT_TIME_FORMAT,
   OPT_DATETIME_FORMAT,
-  OPT_LOG_QUERIES_NOT_USING_INDEXES
+  OPT_LOG_QUERIES_NOT_USING_INDEXES,
+  OPT_PLAN_SEARCH_DEPTH,
+  OPT_HEURISTIC
 };
 
 
@@ -4400,6 +4403,11 @@ log and this option does nothing anymore.",
     "Use stopwords from this file instead of built-in list.",
     (gptr*) &ft_stopword_file, (gptr*) &ft_stopword_file, 0, GET_STR,
     REQUIRED_ARG, 0, 0, 0, 0, 0, 0},
+  {"heuristic", OPT_HEURISTIC,
+   "Controls the heuristic(s) applied during query optimization to prune less-promising partial plans from the optimizer search space. Meaning: 0 - do not apply any heuristic, thus perform exhaustive search; 1 - prune plans based on rows and read time.",
+   (gptr*) &global_system_variables.heuristic,
+   (gptr*) &max_system_variables.heuristic,
+   0, GET_ULONG, OPT_ARG, 1, 0, 1, 0, 1, 0},
 #ifdef HAVE_INNOBASE_DB
   {"innodb_mirrored_log_groups", OPT_INNODB_MIRRORED_LOG_GROUPS,
    "Number of identical copies of log groups we keep for the database. Currently this should be set to 1.",
@@ -4640,6 +4648,11 @@ The minimum value for this variable is 4096.",
    "If this is not 0, then mysqld will use this value to reserve file descriptors to use with setrlimit(). If this value is 0 then mysqld will reserve max_connections*5 or max_connections + table_cache*2 (whichever is larger) number of files.",
    (gptr*) &open_files_limit, (gptr*) &open_files_limit, 0, GET_ULONG,
    REQUIRED_ARG, 0, 0, OS_FILE_LIMIT, 0, 1, 0},
+  {"plan_search_depth", OPT_PLAN_SEARCH_DEPTH,
+   "Maximum depth of search performed by the query optimizer. Values larger than the number of relations in a query result in better query plans, but take longer to compile a query. Smaller values than the number of tables in a relation result in faster optimization, but may produce very bad query plans. If set to 0, the system will automatically pick a reasonable value; if set to MAX_TABLES+2, the optimizer will switch to the original find_best (used for testing/comparison).",
+   (gptr*) &global_system_variables.plan_search_depth,
+   (gptr*) &max_system_variables.plan_search_depth,
+   0, GET_ULONG, OPT_ARG, MAX_TABLES+1, 0, MAX_TABLES+2, 0, 1, 0},
    {"preload_buffer_size", OPT_PRELOAD_BUFFER_SIZE,
     "The size of the buffer that is allocated when preloading indexes",
     (gptr*) &global_system_variables.preload_buff_size,
@@ -4930,6 +4943,7 @@ struct show_var_st status_vars[]= {
    SHOW_KEY_CACHE_LONG},
   {"Key_writes",               (char*) &dflt_key_cache_var.global_cache_write,
    SHOW_KEY_CACHE_LONG},
+  {"Last_query_cost",          (char*) &last_query_cost,        SHOW_DOUBLE},
   {"Max_used_connections",     (char*) &max_used_connections,  SHOW_LONG},
   {"Not_flushed_delayed_rows", (char*) &delayed_rows_in_use,    SHOW_LONG_CONST},
   {"Open_files",               (char*) &my_file_opened,         SHOW_LONG_CONST},

sql/parse_file.cc

@@ -0,0 +1,785 @@
+/* Copyright (C) 2004 MySQL AB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+// Text .frm files management routines
+
+#include "mysql_priv.h"
+#include <errno.h>
+#include <m_ctype.h>
+#include <my_sys.h>
+#include <my_dir.h>
+
+
+/*
+  write string with escaping
+
+  SYNOPSIS
+    write_escaped_string()
+    file	- IO_CACHE for record
+    val_s	- string for writing
+
+  RETURN
+    FALSE - OK
+    TRUE  - error
+*/
+
+static my_bool
+write_escaped_string(IO_CACHE *file, LEX_STRING *val_s)
+{
+  char *eos= val_s->str + val_s->length;
+  char *ptr= val_s->str;
+
+  for (; ptr < eos; ptr++)
+  {
+    /*
+      Should be in sync with read_escaped_string() and
+      parse_quated_escaped_string()
+    */
+    switch(*ptr) {
+    case '\\': // escape character
+      if (my_b_write(file, "\\\\", 2))
+	return TRUE;
+      break;
+    case '\n': // parameter value delimiter
+      if (my_b_write(file, "\\n", 2))
+	return TRUE;
+      break;
+    case '\0': // problem for some string processing utilites
+      if (my_b_write(file, "\\0", 2))
+	return TRUE;
+      break;
+    case 26: // problem for windows utilites (Ctrl-Z)
+      if (my_b_write(file, "\\z", 2))
+	return TRUE;
+      break;
+    case '\'': // list of string delimiter
+      if (my_b_write(file, "\\\'", 2))
+	return TRUE;
+      break;
+    default:
+      if (my_b_write(file, ptr, 1))
+	return TRUE;
+    }
+  }
+  return FALSE;
+}
+
+
+/*
+  write parameter value to IO_CACHE
+
+  SYNOPSIS
+    write_parameter()
+    file	pointer to IO_CACHE structure for writing
+    base	pointer to data structure
+    parameter	pointer to parameter descriptor
+    old_version	for returning back old version number value
+
+  RETURN
+    FALSE - OK
+    TRUE  - error
+*/
+
+static my_bool
+write_parameter(IO_CACHE *file, gptr base, File_option *parameter,
+		ulonglong *old_version)
+{
+  char num_buf[20];			// buffer for numeric operations
+  // string for numeric operations
+  String num(num_buf, sizeof(num_buf), &my_charset_bin);
+  DBUG_ENTER("write_parameter");
+
+  switch (parameter->type) {
+  case FILE_OPTIONS_STRING:
+  {
+    LEX_STRING *val_s= (LEX_STRING *)(base + parameter->offset);
+    if (my_b_write(file, val_s->str, val_s->length))
+      DBUG_RETURN(TRUE);
+    break;
+  }
+  case FILE_OPTIONS_ESTRING:
+  {
+    if (write_escaped_string(file, (LEX_STRING *)(base + parameter->offset)))
+      DBUG_RETURN(TRUE);
+    break;
+  }
+  case FILE_OPTIONS_ULONGLONG:
+  {
+    num.set(*((ulonglong *)(base + parameter->offset)), &my_charset_bin);
+    if (my_b_write(file, num.ptr(), num.length()))
+      DBUG_RETURN(TRUE);
+    break;
+  }
+  case FILE_OPTIONS_REV:
+  {
+    ulonglong *val_i= (ulonglong *)(base + parameter->offset);
+    *old_version= (*val_i)++;
+    num.set(*val_i, &my_charset_bin);
+    if (my_b_write(file, num.ptr(), num.length()))
+      DBUG_RETURN(TRUE);
+    break;
+  }
+  case FILE_OPTIONS_TIMESTAMP:
+  {
+    /* string have to be allocated already */
+    LEX_STRING *val_s= (LEX_STRING *)(base + parameter->offset);
+    time_t tm= time(NULL);
+
+    get_date(val_s->str, GETDATE_DATE_TIME|GETDATE_GMT|GETDATE_FIXEDLENGTH,
+	     tm);
+    val_s->length= PARSE_FILE_TIMESTAMPLENGTH;
+    if (my_b_write(file, val_s->str, PARSE_FILE_TIMESTAMPLENGTH))
+      DBUG_RETURN(TRUE);
+    break;
+  }
+  case FILE_OPTIONS_STRLIST:
+  {
+    List_iterator_fast<LEX_STRING> it(*((List<LEX_STRING>*)
+					(base + parameter->offset)));
+    bool first= 1;
+    LEX_STRING *str;
+    while ((str= it++))
+    {
+      num.set((ulonglong)str->length, &my_charset_bin);
+      // ',' after string to detect list continuation
+      if ((!first && my_b_write(file, " ", 1)) ||
+	  my_b_write(file, "\'", 1) ||
+	  my_b_write(file, str->str, str->length) ||
+	  my_b_write(file, "\'", 1))
+      {
+	DBUG_RETURN(TRUE);
+      }
+      first= 0;
+    }
+    break;
+  }
+  default:
+    DBUG_ASSERT(0); // never should happened
+  }
+  DBUG_RETURN(FALSE);
+}
+
+
+/*
+  write new .frm
+
+  SYNOPSIS
+    sql_create_definition_file()
+    dir			directory where put .frm
+    file		.frm file name
+    type		.frm type string (VIEW, TABLE)
+    base		base address for parameter reading (structure like
+			TABLE)
+    parameters		parameters description
+    max_versions	number of versions to save
+
+  RETURN
+    FALSE - OK
+    TRUE - error
+*/
+
+my_bool
+sql_create_definition_file(const LEX_STRING *dir, const LEX_STRING *file_name,
+			   const LEX_STRING *type,
+			   gptr base, File_option *parameters,
+			   uint max_versions)
+{
+  File handler;
+  IO_CACHE file;
+  char path[FN_REFLEN+1];	// +1 to put temporary file name for sure
+  ulonglong old_version= ULONGLONG_MAX;
+  int path_end;
+  DBUG_ENTER("sql_create_definition_file");
+  DBUG_PRINT("enter", ("Dir: %s, file: %s, base 0x%lx",
+		       dir->str, file_name->str, (ulong) base));
+
+  fn_format(path, file_name->str, dir->str, 0, MY_UNPACK_FILENAME);
+  path_end= strlen(path);
+
+  // temporary file name
+  path[path_end]='~';
+  path[path_end+1]= '\0';
+  if ((handler= my_create(path, CREATE_MODE, O_RDWR | O_TRUNC,
+			  MYF(MY_WME))) <= 0)
+  {
+    DBUG_RETURN(TRUE);
+  }
+
+  if (init_io_cache(&file, handler, 0, SEQ_READ_APPEND, 0L, 0, MYF(MY_WME)))
+    goto err_w_file;
+
+  // write header (file signature)
+  if (my_b_write(&file, "TYPE=", 5) ||
+      my_b_write(&file, type->str, type->length) ||
+      my_b_write(&file, "\n", 1))
+    goto err_w_file;
+
+  // write parameters to temporary file
+  for (File_option *param= parameters; param->name.str; param++)
+  {
+    if (my_b_write(&file, param->name.str, param->name.length) ||
+	my_b_write(&file, "=", 1) ||
+	write_parameter(&file, base, param, &old_version) ||
+	my_b_write(&file, "\n", 1))
+      goto err_w_cache;
+  }
+
+  if (end_io_cache(&file))
+    goto err_w_file;
+
+  if (my_close(handler, MYF(MY_WME)))
+  {
+    DBUG_RETURN(TRUE);
+  }
+
+  // archive copies management
+  path[path_end]='\0';
+  if (!access(path, F_OK))
+  {
+    if (old_version != ULONGLONG_MAX && max_versions != 0)
+    {
+      // save buckup
+      char path_arc[FN_REFLEN];
+      // backup old version
+      char path_to[FN_REFLEN];
+
+      // check archive directory existence
+      fn_format(path_arc, "arc", dir->str, "", MY_UNPACK_FILENAME);
+      if (access(path_arc, F_OK))
+      {
+	if (my_mkdir(path_arc, 0777, MYF(MY_WME)))
+	{
+	  DBUG_RETURN(TRUE);
+	}
+      }
+
+      my_snprintf(path_to, FN_REFLEN, "%s/%s-%04lld",
+		  path_arc, file_name->str, old_version);
+      if (my_rename(path, path_to, MYF(MY_WME)))
+      {
+	DBUG_RETURN(TRUE);
+      }
+
+      // remove very old version
+      if (old_version > max_versions)
+      {
+	my_snprintf(path_to, FN_REFLEN, "%s/%s-%04lld",
+		    path_arc, file_name->str,
+		    old_version - max_versions);
+	if (!access(path_arc, F_OK) && my_delete(path_to, MYF(MY_WME)))
+	{
+	  DBUG_RETURN(TRUE);
+	}
+      }
+    }
+    else
+    {
+      if (my_delete(path, MYF(MY_WME)))	// no backups
+      {
+	DBUG_RETURN(TRUE);
+      }
+    }
+  }
+
+  {
+    // rename temporary file
+    char path_to[FN_REFLEN];
+    memcpy(path_to, path, path_end+1);
+    path[path_end]='~';
+    if (my_rename(path, path_to, MYF(MY_WME)))
+    {
+      DBUG_RETURN(TRUE);
+    }
+  }
+  DBUG_RETURN(FALSE);
+err_w_cache:
+  end_io_cache(&file);
+err_w_file:
+  my_close(handler, MYF(MY_WME));
+  DBUG_RETURN(TRUE);
+}
+
+
+/*
+  Prepare frm to parse (read to memory)
+
+  SYNOPSIS
+    sql_parse_prepare()
+    file_name		- path & filename to .frm file
+    mem_root		- MEM_ROOT for buffer allocation
+    bad_format_errors	- send errors on bad content
+
+  RETURN
+    0 - error
+    parser object
+
+  NOTE
+    returned pointer + 1 will be type of .frm
+*/
+
+File_parser * 
+sql_parse_prepare(const LEX_STRING *file_name, MEM_ROOT *mem_root,
+		  bool bad_format_errors)
+{
+  MY_STAT stat_info;
+  uint len;
+  char *end, *sign;
+  File_parser *parser;
+  File file;
+  DBUG_ENTER("sql__parse_prepare");
+
+  if (!my_stat(file_name->str, &stat_info, MYF(MY_WME)))
+  {
+    DBUG_RETURN(0);
+  }
+
+  if (stat_info.st_size > INT_MAX-1)
+  {
+    my_error(ER_FPARSER_TOO_BIG_FILE, MYF(0), file_name->str);
+    DBUG_RETURN(0);
+  }
+
+  if (!(parser= new(mem_root) File_parser))
+  {
+    DBUG_RETURN(0);
+  }
+
+  if (!(parser->buff= alloc_root(mem_root, stat_info.st_size+1)))
+  {
+    DBUG_RETURN(0);
+  }
+
+  if ((file= my_open(file_name->str, O_RDONLY | O_SHARE, MYF(MY_WME))) < 0)
+  {
+    DBUG_RETURN(0);
+  }
+  
+  if ((len= my_read(file, parser->buff, stat_info.st_size, MYF(MY_WME))) ==
+      MY_FILE_ERROR)
+  {
+    my_close(file, MYF(MY_WME));
+    DBUG_RETURN(0);
+  }
+
+  if (my_close(file, MYF(MY_WME)))
+  {
+    DBUG_RETURN(0);
+  }
+
+  end= parser->end= parser->buff + len;
+  *end= '\0'; // barriaer for more simple parsing
+
+  // 7 = 5 (TYPE=) + 1 (leter at least of type name) + 1 ('\n')
+  if (len < 7 ||
+      parser->buff[0] != 'T' ||
+      parser->buff[1] != 'Y' ||
+      parser->buff[2] != 'P' ||
+      parser->buff[3] != 'E' ||
+      parser->buff[4] != '=')
+    goto frm_error;
+
+  // skip signature;
+  parser->file_type.str= sign= parser->buff + 5;
+  while (*sign >= 'A' && *sign <= 'Z' && sign < end)
+    sign++;
+  if (*sign != '\n')
+    goto frm_error;
+  parser->file_type.length= sign - parser->file_type.str;
+  // EOS for file signature just for safety
+  *sign= '\0';
+
+  parser->start= sign + 1;
+  parser->content_ok= 1;
+
+  DBUG_RETURN(parser);
+
+frm_error:
+  if (bad_format_errors)
+  {
+    my_error(ER_FPARSER_BAD_HEADER, MYF(0), file_name->str);
+    DBUG_RETURN(0);
+  }
+  else
+    DBUG_RETURN(parser); // upper level have to check parser->ok()
+}
+
+
+/*
+  parse LEX_STRING
+
+  SYNOPSIS
+    parse_string()
+    ptr		- pointer on string beginning
+    end		- pointer on symbol after parsed string end (still owned
+		  by buffer and can be accessed
+    mem_root	- MEM_ROOT for parameter allocation
+    str		- pointer on string, where results should be stored
+
+  RETURN
+    0	- error
+    #	- pointer on symbol after string
+*/
+
+static char *
+parse_string(char *ptr, char *end, MEM_ROOT *mem_root, LEX_STRING *str)
+{
+  // get string length
+  char *eol= strchr(ptr, '\n');
+
+  if (eol >= end)
+    return 0;
+
+  str->length= eol - ptr;
+
+  if (!(str->str= alloc_root(mem_root, str->length+1)))
+    return 0;
+
+  memcpy(str->str, ptr, str->length);
+  str->str[str->length]= '\0'; // just for safety
+  return eol+1;
+}
+
+
+/*
+  read escaped string from ptr to eol in already allocated str
+
+  SYNOPSIS
+    parse_escaped_string()
+    ptr		- pointer on string beginning
+    eol		- pointer on character after end of string
+    str		- target string
+
+  RETURN
+    FALSE - OK
+    TRUE  - error
+*/
+
+my_bool
+read_escaped_string(char *ptr, char *eol, LEX_STRING *str)
+{
+  char *write_pos= str->str;
+
+  for(; ptr < eol; ptr++, write_pos++)
+  {
+    char c= *ptr;
+    if (c == '\\')
+    {
+      ptr++;
+      if (ptr >= eol)
+	return TRUE;
+      /*
+	Should be in sync with write_escaped_string() and
+	parse_quated_escaped_string()
+      */
+      switch(*ptr) {
+      case '\\':
+	*write_pos= '\\';
+	break;
+      case 'n':
+	*write_pos= '\n';
+	break;
+      case '0':
+	*write_pos= '\0';
+	break;
+      case 'z':
+	*write_pos= 26;
+	break;
+      case '\'':
+	*write_pos= '\'';
+      default:
+	return TRUE;
+      }
+    }
+    else
+      *write_pos= c;
+  }
+  str->str[str->length= write_pos-str->str]= '\0'; // just for safety
+  return FALSE;
+}
+
+
+/*
+  parse \n delimited escaped string
+
+  SYNOPSIS
+    parse_escaped_string()
+    ptr		- pointer on string beginning
+    end		- pointer on symbol after parsed string end (still owned
+		  by buffer and can be accessed
+    mem_root	- MEM_ROOT for parameter allocation
+    str		- pointer on string, where results should be stored
+
+  RETURN
+    0	- error
+    #	- pointer on symbol after string
+*/
+
+static char *
+parse_escaped_string(char *ptr, char *end, MEM_ROOT *mem_root, LEX_STRING *str)
+{
+  char *eol= strchr(ptr, '\n');
+
+  if (eol == 0 || eol >= end ||
+      !(str->str= alloc_root(mem_root, (eol - ptr) + 1)) ||
+      read_escaped_string(ptr, eol, str))
+    return 0;
+    
+  return eol+1;
+}
+
+
+/*
+  parse '' delimited escaped string
+
+  SYNOPSIS
+    parse_escaped_string()
+    ptr		- pointer on string beginning
+    end		- pointer on symbol after parsed string end (still owned
+		  by buffer and can be accessed
+    mem_root	- MEM_ROOT for parameter allocation
+    str		- pointer on string, where results should be stored
+
+  RETURN
+    0	- error
+    #	- pointer on symbol after string
+*/
+
+static char *
+parse_quated_escaped_string(char *ptr, char *end,
+			    MEM_ROOT *mem_root, LEX_STRING *str)
+{
+  char *eol;
+  uint result_len= 0;
+  bool escaped= 0;
+
+  // starting '
+  if (*(ptr++) != '\'')
+    return 0;
+
+  // find ending '
+  for (eol= ptr; (*eol != '\'' || escaped) && eol < end; eol++)
+  {
+    if (!(escaped= (*eol == '\\' && !escaped)))
+      result_len++;
+  }
+
+  // process string
+  if (eol >= end ||
+      !(str->str= alloc_root(mem_root, result_len + 1)) ||
+      read_escaped_string(ptr, eol, str))
+    return 0;
+
+  return eol+1;
+}
+
+
+/*
+  parse parameters
+ 
+  SYNOPSIS
+    File_parser::parse()
+    base                base address for parameter writing (structure like
+                        TABLE)
+    mem_root            MEM_ROOT for parameters allocation
+    parameters          parameters description
+    required            number of required parameters in above list
+
+  RETURN
+    FALSE - OK
+    TRUE - error
+*/
+
+my_bool
+File_parser::parse(gptr base, MEM_ROOT *mem_root,
+		  struct File_option *parameters, uint required)
+{
+  uint first_param= 0, found= 0;
+  register char *ptr= start;
+  char *eol;
+  LEX_STRING *str;
+  MEM_ROOT *sql_mem;
+  List<LEX_STRING> *list;
+  bool change_mem;
+  DBUG_ENTER("File_parser::parse");
+
+  while (ptr < end && found < required)
+  {
+    char *line= ptr;
+    if (*ptr == '#')
+    {
+      // it is comment
+      if (!(ptr= strchr(ptr, '\n')))
+      {
+	my_error(ER_FPARSER_EOF_IN_COMMENT, MYF(0), line);
+	DBUG_RETURN(TRUE);
+      }
+      ptr++;
+    }
+    else
+    {
+      File_option *parameter= parameters+first_param,
+	*parameters_end= parameters+required;
+      int len= 0;
+      for(; parameter < parameters_end; parameter++)
+      {
+	len= parameter->name.length;
+	// check length
+	if (len < (end-ptr) && ptr[len] != '=')
+	  continue;
+	// check keyword
+	if (memcmp(parameter->name.str, ptr, len) == 0)
+	  break;
+      }
+
+      if (parameter < parameters_end)
+      {
+	found++;
+	/*
+	  if we found first parameter, start search from next parameter
+	  next time.
+	  (this small optimisation should work, because they should be
+	  written in same order)
+	*/
+	if (parameter == parameters+first_param)
+	  first_param++;
+
+	// get value
+	ptr+= (len+1);
+	switch (parameter->type) {
+	case FILE_OPTIONS_STRING:
+	{
+	  if (!(ptr= parse_string(ptr, end, mem_root,
+				  (LEX_STRING *)(base +
+						 parameter->offset))))
+	  {
+	    my_error(ER_FPARSER_ERROR_IN_PARAMETER, MYF(0),
+		     parameter->name.str, line);
+	    DBUG_RETURN(TRUE);
+	  }
+	  break;
+	}
+	case FILE_OPTIONS_ESTRING:
+	{
+	  if (!(ptr= parse_escaped_string(ptr, end, mem_root,
+					  (LEX_STRING *)
+					  (base + parameter->offset))))
+	  {
+	    my_error(ER_FPARSER_ERROR_IN_PARAMETER, MYF(0),
+		     parameter->name.str, line);
+	    DBUG_RETURN(TRUE);
+	    DBUG_RETURN(TRUE);
+	  }
+	  break;
+	}
+	case FILE_OPTIONS_ULONGLONG:
+	case FILE_OPTIONS_REV:
+	  if (!(eol= strchr(ptr, '\n')))
+	  {
+	    my_error(ER_FPARSER_ERROR_IN_PARAMETER, MYF(0),
+		     parameter->name.str, line);
+	    DBUG_RETURN(TRUE);
+	  }
+	  *eol= '\0';
+	  *((ulonglong*)(base + parameter->offset))= atoll(ptr);
+	  *eol= '\n';
+	  ptr= eol+1;
+	  break;
+	case FILE_OPTIONS_TIMESTAMP:
+	{
+	  /* string have to be allocated already */
+	  LEX_STRING *val= (LEX_STRING *)(base + parameter->offset);
+	  /* yyyy-mm-dd HH:MM:SS = 19(PARSE_FILE_TIMESTAMPLENGTH) characters */
+	  if (ptr[PARSE_FILE_TIMESTAMPLENGTH] != '\n')
+	  {
+	    my_error(ER_FPARSER_ERROR_IN_PARAMETER, MYF(0),
+		     parameter->name.str, line);
+	    DBUG_RETURN(TRUE);
+	  }
+	  memcpy(val->str, ptr, PARSE_FILE_TIMESTAMPLENGTH);
+	  val->str[val->length= PARSE_FILE_TIMESTAMPLENGTH]= '\0';
+	  ptr+= (PARSE_FILE_TIMESTAMPLENGTH+1);
+	  break;
+	}
+	case FILE_OPTIONS_STRLIST:
+	{
+	  /*
+	    TODO: remove play with mem_root, when List will be able
+	    to store MEM_ROOT* pointer for list elements allocation
+	  */
+	  sql_mem= my_pthread_getspecific_ptr(MEM_ROOT*, THR_MALLOC);
+	  list= (List<LEX_STRING>*)(base + parameter->offset);
+	  if ((change_mem= (sql_mem != mem_root)))
+	  {
+	    change_mem= 1;
+	    my_pthread_setspecific_ptr(THR_MALLOC, mem_root);
+	  }
+	    
+	  list->empty();
+	  // list parsing
+	  while (ptr < end)
+	  {
+	    if (!(str= (LEX_STRING*)alloc_root(mem_root,
+					       sizeof(LEX_STRING))) ||
+		list->push_back(str))
+	      goto list_err;
+	    if(!(ptr= parse_quated_escaped_string(ptr, end, mem_root, str)))
+	      goto list_err_w_message;
+	    switch (*ptr) {
+	    case '\n':
+	      goto end_of_list;
+	    case ' ':
+	      // we cant go over buffer bounds, because we have \0 at the end
+	      ptr++;
+	      break;
+	    default:
+	      goto list_err_w_message;
+	    }
+	  }
+	end_of_list:
+	  if (*(ptr++) != '\n')
+	    goto list_err;
+
+	  if (change_mem)
+	    my_pthread_setspecific_ptr(THR_MALLOC, sql_mem);
+	  break;
+
+      list_err_w_message:
+	  my_error(ER_FPARSER_ERROR_IN_PARAMETER, MYF(0),
+		     parameter->name.str, line);
+      list_err:
+	  if (change_mem)
+	    my_pthread_setspecific_ptr(THR_MALLOC, sql_mem);
+	  DBUG_RETURN(TRUE);
+	}
+	default:
+	  DBUG_ASSERT(0); // never should happened
+	}
+      }
+      else
+      {
+	// skip unknown parameter
+	if (!(ptr= strchr(ptr, '\n')))
+	{
+	  my_error(ER_FPARSER_EOF_IN_UNKNOWN_PARAMETER, MYF(0),
+		   line);
+	  DBUG_RETURN(TRUE);
+	}
+	ptr++;
+      }
+    }
+  }
+  DBUG_RETURN(FALSE);
+}

sql/parse_file.h

@@ -0,0 +1,68 @@
+/* -*- C++ -*- */
+/* Copyright (C) 2004 MySQL AB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+#ifndef _PARSE_FILE_H_
+#define _PARSE_FILE_H_
+
+#define PARSE_FILE_TIMESTAMPLENGTH 19
+
+typedef enum {
+  FILE_OPTIONS_STRING,		/* String (LEX_STRING) */
+  FILE_OPTIONS_ESTRING,		/* Escaped string (LEX_STRING) */
+  FILE_OPTIONS_ULONGLONG,	/* ulonglong parapeter (ulonglong) */
+  FILE_OPTIONS_REV,		/* Revision version number (ulonglong) */
+  FILE_OPTIONS_TIMESTAMP,	/* timestamp (LEX_STRING have to be
+				   allocated with length 20 (19+1) */
+  FILE_OPTIONS_STRLIST		/* list of strings (List<char*>) */
+} file_opt_type;
+  
+struct File_option
+{
+  const LEX_STRING name;		/* Name of the option */
+  int offset;				/* offset to base address of value */
+  enum file_opt_type type;		/* Option type */
+};
+
+class File_parser;
+File_parser *sql_parse_prepare(const LEX_STRING *file_name,
+			       MEM_ROOT *mem_root);
+
+my_bool
+sql_create_definition_file(const LEX_STRING *dir, const  LEX_STRING *file_name,
+			   const LEX_STRING *type,
+			   gptr base, File_option *parameters, uint versions);
+
+class File_parser: public Sql_alloc
+{
+  char *buff, *start, *end;
+  LEX_STRING file_type;
+  my_bool content_ok;
+public:
+  File_parser() :buff(0), start(0), end(0), content_ok(0)
+    { file_type.str= 0; file_type.length= 0; }
+
+  my_bool ok() { return content_ok; }
+  LEX_STRING *type() { return &file_type; }
+  my_bool parse(gptr base, MEM_ROOT *mem_root,
+		struct File_option *parameters, uint required);
+
+  friend File_parser *sql_parse_prepare(const LEX_STRING *file_name,
+					MEM_ROOT *mem_root,
+					bool bad_format_errors);
+};
+
+#endif /* _PARSE_FILE_H_ */

sql/set_var.cc

@@ -160,6 +160,7 @@ sys_var_str             sys_ft_boolean_syntax("ft_boolean_syntax",
                                          sys_update_ftb_syntax,
                                          sys_default_ftb_syntax,
                                          ft_boolean_syntax);
+sys_var_thd_ulong       sys_heuristic("heuristic", &SV::heuristic);
 sys_var_str             sys_init_connect("init_connect", 0,
                                          sys_update_init_connect,
                                          sys_default_init_connect,0);
@@ -262,6 +263,8 @@ sys_var_thd_ulong	sys_net_retry_count("net_retry_count",
 					    0, fix_net_retry_count);
 sys_var_thd_bool	sys_new_mode("new", &SV::new_mode);
 sys_var_thd_bool	sys_old_passwords("old_passwords", &SV::old_passwords);
+sys_var_thd_ulong       sys_plan_search_depth("plan_search_depth",
+                                              &SV::plan_search_depth);
 sys_var_thd_ulong       sys_preload_buff_size("preload_buffer_size",
                                               &SV::preload_buff_size);
 sys_var_thd_ulong	sys_read_buff_size("read_buffer_size",
@@ -488,6 +491,7 @@ sys_var *sys_variables[]=
   &sys_ft_boolean_syntax,
   &sys_foreign_key_checks,
   &sys_group_concat_max_len,
+  &sys_heuristic,
   &sys_identity,
   &sys_init_connect,
   &sys_init_slave,
@@ -536,6 +540,7 @@ sys_var *sys_variables[]=
   &sys_net_write_timeout,
   &sys_new_mode,
   &sys_old_passwords,
+  &sys_plan_search_depth,
   &sys_preload_buff_size,
   &sys_pseudo_thread_id,
   &sys_query_alloc_block_size,
@@ -812,6 +817,8 @@ struct show_var_st init_vars[]= {
   {"version_compile_machine", (char*) MACHINE_TYPE,		    SHOW_CHAR},
   {sys_os.name,		      (char*) &sys_os,			    SHOW_SYS},
   {sys_net_wait_timeout.name, (char*) &sys_net_wait_timeout,	    SHOW_SYS},
+  {sys_heuristic.name,        (char*) &sys_heuristic,               SHOW_SYS},
+  {sys_plan_search_depth.name,(char*) &sys_plan_search_depth,       SHOW_SYS},
   {NullS, NullS, SHOW_LONG}
 };
 

sql/share/czech/errmsg.txt

@@ -345,3 +345,8 @@ character-set=latin2
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/danish/errmsg.txt

@@ -339,3 +339,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/dutch/errmsg.txt

@@ -347,3 +347,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/english/errmsg.txt

@@ -336,3 +336,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/estonian/errmsg.txt

@@ -341,3 +341,8 @@ character-set=latin7
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/french/errmsg.txt

@@ -336,3 +336,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/german/errmsg.txt

@@ -348,3 +348,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/greek/errmsg.txt

@@ -336,3 +336,8 @@ character-set=greek
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/hungarian/errmsg.txt

@@ -338,3 +338,8 @@ character-set=latin2
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/italian/errmsg.txt

@@ -336,3 +336,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/japanese/errmsg.txt

@@ -338,3 +338,8 @@ character-set=ujis
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/korean/errmsg.txt

@@ -336,3 +336,8 @@ character-set=euckr
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/norwegian-ny/errmsg.txt

@@ -338,3 +338,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/norwegian/errmsg.txt

@@ -338,3 +338,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/polish/errmsg.txt

@@ -340,3 +340,8 @@ character-set=latin2
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/portuguese/errmsg.txt

@@ -337,3 +337,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/romanian/errmsg.txt

@@ -340,3 +340,8 @@ character-set=latin2
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/russian/errmsg.txt

@@ -338,3 +338,8 @@ character-set=koi8r
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"<22><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> '%-.64s'"
+"<22><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> '%-.64s'"
+"<22><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> '%-.64s'"
+"<22><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> '%-.64s' (<28><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>: '%-.64s')"
+"<22><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> '%-.64s'"

sql/share/serbian/errmsg.txt

@@ -330,3 +330,8 @@ character-set=cp1250
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/slovak/errmsg.txt

@@ -344,3 +344,8 @@ character-set=latin2
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/spanish/errmsg.txt

@@ -338,3 +338,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/swedish/errmsg.txt

@@ -336,3 +336,8 @@ character-set=latin1
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"Configuration file '%-.64s' is too big"
+"Malformed file type header in file '%-.64s'"
+"Unexpected end of file during parsing comment '%-.64s'"
+"Error during parsing parameter '%-.64s' (line: '%-.64s')"
+"Unexpected end of file during skipping unknown parameter '%-.64s'"

sql/share/ukrainian/errmsg.txt

@@ -341,3 +341,8 @@ character-set=koi8u
 "Variable or condition declaration after cursor or handler declaration"
 "Cursor declaration after handler declaration"
 "Case not found for CASE statement"
+"<22><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD>Ʀ<EFBFBD><C6A6><EFBFBD><EFBFBD>æ<EFBFBD><C3A6><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> '%-.64s'"
+"<22><>צ<EFBFBD><D7A6><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> <20> <20><><EFBFBD>̦ '%-.64s'"
+"<22><><EFBFBD><EFBFBD><EFBFBD>Ħ<EFBFBD><C4A6><EFBFBD><EFBFBD><EFBFBD><EFBFBD> ˦<><CBA6><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҧ '%-.64s'"
+"<22><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD>Ц<EFBFBD><D0A6><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Φ <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> '%-.64s' (<28><><EFBFBD><EFBFBD><EFBFBD>: '%-.64s')"
+"<22><><EFBFBD><EFBFBD><EFBFBD>Ħ<EFBFBD><C4A6><EFBFBD><EFBFBD><EFBFBD><EFBFBD> ˦<><CBA6><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD> <20> <20><><EFBFBD><EFBFBD>¦ <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><>צ<EFBFBD><D7A6><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> '%-.64s'"

sql/sql_class.h

@@ -392,6 +392,8 @@ struct system_variables
   ulong table_type;
   ulong tmp_table_size;
   ulong tx_isolation;
+  ulong heuristic;
+  ulong plan_search_depth;
   /* Determines which non-standard SQL behaviour should be enabled */
   ulong sql_mode;
   ulong default_week_format;

sql/sql_select.cc

@@ -48,7 +48,25 @@ static int sort_keyuse(KEYUSE *a,KEYUSE *b);
 static void set_position(JOIN *join,uint index,JOIN_TAB *table,KEYUSE *key);
 static bool create_ref_for_key(JOIN *join, JOIN_TAB *j, KEYUSE *org_keyuse,
 			       table_map used_tables);
-static void find_best_combination(JOIN *join,table_map rest_tables);
+static void choose_plan(JOIN *join,table_map join_tables);
+
+static void best_access_path(JOIN *join, JOIN_TAB *s, THD *thd,
+                             table_map remaining_tables, uint idx,
+                             double record_count, double read_time);
+static void optimize_straight_join(JOIN *join, table_map join_tables);
+static void greedy_search(JOIN *join, table_map remaining_tables,
+                             uint depth, uint heuristic);
+static void best_extension_by_limited_search(JOIN *join,
+                                             table_map remaining_tables,
+                                             uint idx, double record_count,
+                                             double read_time, uint depth,
+                                             uint heuristic);
+static uint determine_search_depth(JOIN* join);
+static int join_tab_cmp(const void* ptr1, const void* ptr2);
+/*
+  TODO: 'find_best' is here only temporarily until 'greedy_search' is
+  tested and approved.
+*/
 static void find_best(JOIN *join,table_map rest_tables,uint index,
 		      double record_count,double read_time);
 static uint cache_record_length(JOIN *join,uint index);
@@ -2002,7 +2020,7 @@ make_join_statistics(JOIN *join,TABLE_LIST *tables,COND *conds,
   if (join->const_tables != join->tables)
   {
     optimize_keyuse(join, keyuse_array);
-    find_best_combination(join,all_table_map & ~join->const_table_map);
+    choose_plan(join, all_table_map & ~join->const_table_map);
   }
   else
   {
@@ -2579,7 +2597,7 @@ update_ref_and_keys(THD *thd, DYNAMIC_ARRAY *keyuse,JOIN_TAB *join_tab,
 }
 
 /*
-  Update some values in keyuse for faster find_best_combination() loop
+  Update some values in keyuse for faster choose_plan() loop
 */
 
 static void optimize_keyuse(JOIN *join, DYNAMIC_ARRAY *keyuse_array)
@@ -2647,16 +2665,952 @@ set_position(JOIN *join,uint idx,JOIN_TAB *table,KEYUSE *key)
 }
 
 
+/*
+  Find the best access path for an extension of a partial execution plan and
+  add this path to the plan.
+
+  SYNOPSIS
+    best_access_path()
+    join             pointer to the structure providing all context info
+                     for the query
+    s                the table to be joined by the function
+    thd              thread for the connection that submitted the query
+    remaining_tables set of tables not included into the partial plan yet
+    idx              the length of the partial plan
+    record_count     estimate for the number of records returned by the partial
+                     plan
+    read_time        the cost of the partial plan
+
+  DESCRIPTION
+    The function finds the best access path to table 's' from the passed
+    partial plan where an access path is the general term for any means to
+    access the data in 's'. An access path may use either an index or a scan,
+    whichever is cheaper. The input partial plan is passed via the array
+    'join->positions' of length 'idx'. The chosen access method for 's' and its
+    cost are stored in 'join->positions[idx]'.
+
+  RETURN
+    None
+*/
+
 static void
-find_best_combination(JOIN *join, table_map rest_tables)
+best_access_path(JOIN      *join,
+                 JOIN_TAB  *s,
+                 THD       *thd,
+                 table_map remaining_tables,
+                 uint      idx,
+                 double    record_count,
+                 double    read_time)
 {
-  DBUG_ENTER("find_best_combination");
+  KEYUSE *best_key=         0;
-  join->best_read=DBL_MAX;
+  uint best_max_key_part=   0;
-  find_best(join,rest_tables, join->const_tables,1.0,0.0);
+  my_bool found_constraint= 0;
+  double best=              DBL_MAX;
+  double best_time=         DBL_MAX;
+  double records=           DBL_MAX;
+  double tmp;
+  ha_rows rec;
+
+  DBUG_ENTER("best_access_path");
+
+  if (s->keyuse)
+  {                                            /* Use key if possible */
+    TABLE *table= s->table;
+    KEYUSE *keyuse,*start_key=0;
+    double best_records= DBL_MAX;
+    uint max_key_part=0;
+
+    /* Test how we can use keys */
+    rec= s->records/MATCHING_ROWS_IN_OTHER_TABLE;  // Assumed records/key
+    for (keyuse=s->keyuse ; keyuse->table == table ;)
+    {
+      key_part_map found_part= 0;
+      table_map found_ref=     0;
+      uint found_ref_or_null=  0;
+      uint key=     keyuse->key;
+      KEY *keyinfo= table->key_info+key;
+      bool ft_key=  (keyuse->keypart == FT_KEYPART);
+
+      /* Calculate how many key segments of the current key we can use */
+      start_key= keyuse;
+      do
+      { /* for each keypart */
+        uint keypart= keyuse->keypart;
+        uint found_part_ref_or_null= KEY_OPTIMIZE_REF_OR_NULL;
+        do
+        {
+          if (!(remaining_tables & keyuse->used_tables) &&
+              !(found_ref_or_null & keyuse->optimize))
+          {
+            found_part|= keyuse->keypart_map;
+            found_ref|=  keyuse->used_tables;
+            if (rec > keyuse->ref_table_rows)
+              rec= keyuse->ref_table_rows;
+            found_part_ref_or_null&= keyuse->optimize;
+          }
+          keyuse++;
+          found_ref_or_null|= found_part_ref_or_null;
+        } while (keyuse->table == table && keyuse->key == key &&
+                 keyuse->keypart == keypart);
+      } while (keyuse->table == table && keyuse->key == key);
+
+      /*
+        Assume that that each key matches a proportional part of table.
+      */
+      if (!found_part && !ft_key)
+        continue;                               // Nothing usable found
+
+      if (rec < MATCHING_ROWS_IN_OTHER_TABLE)
+        rec= MATCHING_ROWS_IN_OTHER_TABLE;      // Fix for small tables
+
+      /*
+        ft-keys require special treatment
+      */
+      if (ft_key)
+      {
+        /*
+          Really, there should be records=0.0 (yes!)
+          but 1.0 would be probably safer
+        */
+        tmp= prev_record_reads(join, found_ref);
+        records= 1.0;
+      }
+      else
+      {
+        found_constraint= 1;
+        /*
+          Check if we found full key
+        */
+        if (found_part == PREV_BITS(uint,keyinfo->key_parts) &&
+            !found_ref_or_null)
+        {                                         /* use eq key */
+          max_key_part= (uint) ~0;
+          if ((keyinfo->flags & (HA_NOSAME | HA_NULL_PART_KEY)) == HA_NOSAME)
+          {
+            tmp = prev_record_reads(join, found_ref);
+            records=1.0;
+          }
+          else
+          {
+            if (!found_ref)
+            {                                     /* We found a const key */
+              if (table->quick_keys.is_set(key))
+                records= (double) table->quick_rows[key];
+              else
+              {
+                /* quick_range couldn't use key! */
+                records= (double) s->records/rec;
+              }
+            }
+            else
+            {
+              if (!(records=keyinfo->rec_per_key[keyinfo->key_parts-1]))
+              {                                   /* Prefer longer keys */
+                records=
+                  ((double) s->records / (double) rec *
+                   (1.0 +
+                    ((double) (table->max_key_length-keyinfo->key_length) /
+                     (double) table->max_key_length)));
+                if (records < 2.0)
+                  records=2.0;               /* Can't be as good as a unique */
+              }
+            }
+            /* Limit the number of matched rows */
+            tmp = records;
+            set_if_smaller(tmp, (double) thd->variables.max_seeks_for_key);
+            if (table->used_keys.is_set(key))
+            {
+              /* we can use only index tree */
+              uint keys_per_block= table->file->block_size/2/
+                (keyinfo->key_length+table->file->ref_length)+1;
+              tmp = record_count*(tmp+keys_per_block-1)/keys_per_block;
+            }
+            else
+              tmp = record_count*min(tmp,s->worst_seeks);
+          }
+        }
+        else
+        {
+          /*
+            Use as much key-parts as possible and a uniq key is better
+            than a not unique key
+            Set tmp to (previous record count) * (records / combination)
+          */
+          if ((found_part & 1) &&
+              (!(table->file->index_flags(key) & HA_ONLY_WHOLE_INDEX) ||
+               found_part == PREV_BITS(uint,keyinfo->key_parts)))
+          {
+            max_key_part=max_part_bit(found_part);
+            /*
+              Check if quick_range could determinate how many rows we
+              will match
+            */
+            if (table->quick_keys.is_set(key) &&
+                table->quick_key_parts[key] == max_key_part)
+              tmp= records= (double) table->quick_rows[key];
+            else
+            {
+              /* Check if we have statistic about the distribution */
+              if ((records = keyinfo->rec_per_key[max_key_part-1]))
+                tmp = records;
+              else
+              {
+                /*
+                  Assume that the first key part matches 1% of the file
+                  and that the hole key matches 10 (duplicates) or 1
+                  (unique) records.
+                  Assume also that more key matches proportionally more
+                  records
+                  This gives the formula:
+                  records = (x * (b-a) + a*c-b)/(c-1)
+
+                  b = records matched by whole key
+                  a = records matched by first key part (10% of all records?)
+                  c = number of key parts in key
+                  x = used key parts (1 <= x <= c)
+                */
+                double rec_per_key;
+                if (!(rec_per_key=(double)
+                      keyinfo->rec_per_key[keyinfo->key_parts-1]))
+                  rec_per_key=(double) s->records/rec+1;
+
+                if (!s->records)
+                  tmp = 0;
+                else if (rec_per_key/(double) s->records >= 0.01)
+                  tmp = rec_per_key;
+                else
+                {
+                  double a=s->records*0.01;
+                  tmp = (max_key_part * (rec_per_key - a) +
+                         a*keyinfo->key_parts - rec_per_key)/
+                    (keyinfo->key_parts-1);
+                  set_if_bigger(tmp,1.0);
+                }
+                records = (ulong) tmp;
+              }
+              /*
+                If quick_select was used on a part of this key, we know
+                the maximum number of rows that the key can match.
+              */
+              if (table->quick_keys.is_set(key) &&
+                  table->quick_key_parts[key] <= max_key_part &&
+                  records > (double) table->quick_rows[key])
+                tmp= records= (double) table->quick_rows[key];
+              else if (found_ref_or_null)
+              {
+                /* We need to do two key searches to find key */
+                tmp *= 2.0;
+                records *= 2.0;
+              }
+            }
+            /* Limit the number of matched rows */
+            set_if_smaller(tmp, (double) thd->variables.max_seeks_for_key);
+            if (table->used_keys.is_set(key))
+            {
+              /* we can use only index tree */
+              uint keys_per_block= table->file->block_size/2/
+                (keyinfo->key_length+table->file->ref_length)+1;
+              tmp = record_count*(tmp+keys_per_block-1)/keys_per_block;
+            }
+            else
+              tmp = record_count*min(tmp,s->worst_seeks);
+          }
+          else
+            tmp = best_time;                    // Do nothing
+        }
+      } /* not ft_key */
+      if (tmp < best_time - records/(double) TIME_FOR_COMPARE)
+      {
+        best_time= tmp + records/(double) TIME_FOR_COMPARE;
+        best= tmp;
+        best_records= records;
+        best_key= start_key;
+        best_max_key_part= max_key_part;
+      }
+    }
+    records= best_records;
+  }
+
+  /*
+    Don't test table scan if it can't be better.
+    Prefer key lookup if we would use the same key for scanning.
+
+    Don't do a table scan on InnoDB tables, if we can read the used
+    parts of the row from any of the used index.
+    This is because table scans uses index and we would not win
+    anything by using a table scan.
+  */
+  if ((records >= s->found_records || best > s->read_time) &&
+      !(s->quick && best_key && s->quick->index == best_key->key &&
+        best_max_key_part >= s->table->quick_key_parts[best_key->key]) &&
+      !((s->table->file->table_flags() & HA_TABLE_SCAN_ON_INDEX) &&
+        ! s->table->used_keys.is_clear_all() && best_key) &&
+      !(s->table->force_index && best_key))
+  {                                             // Check full join
+    ha_rows rnd_records= s->found_records;
+    /*
+      If there is a restriction on the table, assume that 25% of the
+      rows can be skipped on next part.
+      This is to force tables that this table depends on before this
+      table
+    */
+    if (found_constraint)
+      rnd_records-= rnd_records/4;
+
+    /*
+      Range optimizer never proposes a RANGE if it isn't better
+      than FULL: so if RANGE is present, it's always preferred to FULL.
+      Here we estimate its cost.
+    */
+    if (s->quick)
+    {
+      /*
+        For each record we:
+        - read record range through 'quick'
+        - skip rows which does not satisfy WHERE constraints
+      */
+      tmp= record_count *
+        (s->quick->read_time +
+         (s->found_records - rnd_records)/(double) TIME_FOR_COMPARE);
+    }
+    else
+    {
+      /* Estimate cost of reading table. */
+      tmp= s->table->file->scan_time();
+      if (s->on_expr)                         // Can't use join cache
+      {
+        /*
+          For each record we have to:
+          - read the whole table record 
+          - skip rows which does not satisfy join condition
+        */
+        tmp= record_count *
+          (tmp +
+           (s->records - rnd_records)/(double) TIME_FOR_COMPARE);
+      }
+      else
+      {
+        /* We read the table as many times as join buffer becomes full. */
+        tmp*= (1.0 + floor((double) cache_record_length(join,idx) *
+                           record_count /
+                           (double) thd->variables.join_buff_size));
+        /* 
+            We don't make full cartesian product between rows in the scanned
+           table and existing records because we skip all rows from the
+           scanned table, which does not satisfy join condition when 
+           we read the table (see flush_cached_records for details). Here we
+           take into account cost to read and skip these records.
+        */
+        tmp+= (s->records - rnd_records)/(double) TIME_FOR_COMPARE;
+      }
+    }
+
+    /*
+      We estimate the cost of evaluating WHERE clause for found records
+      as record_count * rnd_records / TIME_FOR_COMPARE. This cost plus
+      tmp give us total cost of using TABLE SCAN
+    */
+    if (best == DBL_MAX ||
+        (tmp  + record_count/(double) TIME_FOR_COMPARE*rnd_records <
+         best + record_count/(double) TIME_FOR_COMPARE*records))
+    {
+      /*
+        If the table has a range (s->quick is set) make_join_select()
+        will ensure that this will be used
+      */
+      best= tmp;
+      records= rows2double(rnd_records);
+      best_key= 0;
+    }
+  }
+
+  /* Update the cost information for the current partial plan */
+  join->positions[idx].records_read= records;
+  join->positions[idx].read_time=    best;
+  join->positions[idx].key=          best_key;
+  join->positions[idx].table=        s;
+
+  if (!best_key &&
+      idx == join->const_tables &&
+      s->table == join->sort_by_table &&
+      join->unit->select_limit_cnt >= records)
+    join->sort_by_table= (TABLE*) 1;  // Must use temporary table
+
   DBUG_VOID_RETURN;
 }
 
 
+/*
+  Selects and invokes a search strategy for an optimal query plan.
+
+  SYNOPSIS
+    choose_plan()
+    join        pointer to the structure providing all context info for
+                the query
+    join_tables set of the tables in the query
+
+  DESCRIPTION
+    The function checks user-configurable parameters that control the search
+    strategy for an optimal plan, selects the search method and then invokes
+    it. Each specific optimization procedure stores the final optimal plan in
+    the array 'join->best_positions', and the cost of the plan in
+    'join->best_read'.
+
+  RETURN
+    None
+*/
+
+static void
+choose_plan(JOIN *join, table_map join_tables)
+{
+  uint search_depth= join->thd->variables.plan_search_depth;
+  uint heuristic=    join->thd->variables.heuristic;
+
+  DBUG_ENTER("choose_plan");
+
+  if (join->select_options & SELECT_STRAIGHT_JOIN)
+  {
+    optimize_straight_join(join, join_tables);
+  }
+  else
+  {
+    /*
+      Heuristic: pre-sort all access plans with respect to the number of
+      records accessed.
+    */
+    qsort(join->best_ref + join->const_tables, join->tables - join->const_tables,
+          sizeof(JOIN_TAB*), join_tab_cmp);
+
+    if (search_depth == MAX_TABLES+2)
+    { /*
+        TODO: 'MAX_TABLES+2' denotes the old implementation of find_best before
+        the greedy version. Will be removed when greedy_search is approved.
+      */
+      join->best_read= DBL_MAX;
+      find_best(join, join_tables, join->const_tables, 1.0, 0.0);
+    } 
+    else
+    {
+      if (search_depth == 0)
+        /* Automatically determine a reasonable value for 'search_depth' */
+        search_depth= determine_search_depth(join);
+      greedy_search(join, join_tables, search_depth, heuristic);
+    }
+  }
+
+  /* Store the cost of this query into a user variable */
+  last_query_cost= join->best_read;
+
+  DBUG_VOID_RETURN;
+}
+
+
+/*
+  Compare two JOIN_TAB objects based on the number of accessed records.
+
+  SYNOPSIS
+    join_tab_cmp()
+    ptr1 pointer to first JOIN_TAB object
+    ptr2 pointer to second JOIN_TAB object
+
+  RETURN
+    1  if first is bigger
+    -1 if second is bigger
+    0  if equal
+*/
+
+static int
+join_tab_cmp(const void* ptr1, const void* ptr2)
+{
+  JOIN_TAB *jt1= *(JOIN_TAB**) ptr1;
+  JOIN_TAB *jt2= *(JOIN_TAB**) ptr2;
+  if (jt1->found_records > jt2->found_records)
+    return 1;
+  else if (jt1->found_records < jt2->found_records)
+    return -1;
+  else
+    return 0;
+}
+
+
+/*
+  Heuristic procedure to automatically guess a reasonable degree of
+  exhaustiveness for the greedy search procedure.
+
+  SYNOPSIS
+    determine_search_depth()
+    join   pointer to the structure providing all context info for the query
+
+  DESCRIPTION
+    The procedure estimates the optimization time and selects a search depth
+    big enough to result in a near-optimal QEP, that doesn't take too long to
+    find. If the number of tables in the query exceeds some constant, then
+    search_depth is set to this constant.
+
+  NOTES
+    This is an extremely simplistic implementation that serves as a stub for a
+    more advanced analysis of the join. Ideally the search depth should be
+    determined by learning from previous query optimizations, because it will
+    depend on the CPU power (and other factors).
+
+  RETURN
+    A positive integer that specifies the search depth (and thus the
+    exhaustiveness) of the depth-first search algorithm used by
+    'greedy_search'.
+*/
+
+static uint
+determine_search_depth(JOIN *join)
+{
+  uint table_count=  join->tables - join->const_tables;
+  uint search_depth;
+  /* TODO: this value should be determined dynamically, based on statistics: */
+  uint max_tables_for_exhaustive_opt= 7;
+
+  if (table_count <= max_tables_for_exhaustive_opt)
+    search_depth= table_count+1; // use exhaustive for small number of tables
+  else
+    /*
+      TODO: this value could be determined by some mapping of the form:
+      depth : table_count -> [max_tables_for_exhaustive_opt..MAX_EXHAUSTIVE]
+    */
+    search_depth= max_tables_for_exhaustive_opt; // use greedy search
+
+  return search_depth;
+}
+
+
+/*
+  Select the best ways to access the tables in a query without reordering them.
+
+  SYNOPSIS
+    optimize_straight_join()
+    join          pointer to the structure providing all context info for
+                  the query
+    join_tables   set of the tables in the query
+
+  DESCRIPTION
+    Find the best access paths for each query table and compute their costs
+    according to their order in the array 'join->best_ref' (thus without
+    reordering the join tables). The function calls sequentially
+    'best_access_path' for each table in the query to select the best table
+    access method. The final optimal plan is stored in the array
+    'join->best_positions', and the corresponding cost in 'join->best_read'.
+
+  NOTES
+    This function can be applied to:
+    - queries with STRAIGHT_JOIN
+    - internally to compute the cost of an arbitrary QEP
+    Thus 'optimize_straight_join' can be used at any stage of the query
+    optimization process to finalize a QEP as it is.
+
+  RETURN
+    None
+*/
+
+static void
+optimize_straight_join(JOIN *join, table_map join_tables)
+{
+  JOIN_TAB *s;
+  uint idx= join->const_tables;
+  double    record_count= 1.0;
+  double    read_time=    0.0;
+
+  for (JOIN_TAB **pos= join->best_ref + idx ; (s= *pos) ; pos++)
+  {
+    /* Find the best access method from 's' to the current partial plan */
+    best_access_path(join, s, join->thd, join_tables, idx, record_count, read_time);
+    /* compute the cost of the new plan extended with 's' */
+    record_count*= join->positions[idx].records_read;
+    read_time+=    join->positions[idx].read_time;
+    join_tables&= ~(s->table->map);
+    ++idx;
+  }
+
+  read_time+= record_count / (double) TIME_FOR_COMPARE;
+  if (join->sort_by_table &&
+      join->sort_by_table != join->positions[join->const_tables].table->table)
+    read_time+= record_count;  // We have to make a temp table
+  memcpy((gptr) join->best_positions, (gptr) join->positions,
+         sizeof(POSITION)*idx);
+  join->best_read= read_time;
+}
+
+
+/*
+  Find a good, possibly optimal, query execution plan (QEP) by a greedy search.
+
+  SYNOPSIS
+    join             pointer to the structure providing all context info
+                     for the query
+    remaining_tables set of tables not included into the partial plan yet
+    search_depth     controlls the exhaustiveness of the search
+    heuristic        the pruning heuristics that should be applied during
+                     search
+
+  DESCRIPTION
+    The search procedure uses a hybrid greedy/exhaustive search with controlled
+    exhaustiveness. The search is performed in N = card(remaining_tables)
+    steps. Each step evaluates how promising is each of the unoptimized tables,
+    selects the most promising table, and extends the current partial QEP with
+    that table.  Currenly the most 'promising' table is the one with least
+    expensive extension.
+    There are two extreme cases:
+    1. When (card(remaining_tables) < search_depth), the estimate finds the best
+       complete continuation of the partial QEP. This continuation can be
+       used directly as a result of the search.
+    2. When (search_depth == 1) the 'best_extension_by_limited_search'
+       consideres the extension of the current QEP with each of the remaining
+       unoptimized tables.
+    All other cases are in-between these two extremes. Thus the parameter
+    'search_depth' controlls the exhaustiveness of the search. The higher the
+    value, the longer the optimizaton time and possibly the better the
+    resulting plan. The lower the value, the fewer alternative plans are
+    estimated, but the more likely to get a bad QEP.
+
+    All intermediate and final results of the procedure are stored in 'join':
+    join->positions      modified for every partial QEP that is explored
+    join->best_positions modified for the current best complete QEP
+    join->best_read      modified for the current best complete QEP
+    join->best_ref       might be partially reordered
+    The final optimal plan is stored in 'join->best_positions', and its
+    corresponding cost in 'join->best_read'.
+
+  NOTES
+    The following pseudocode describes the algorithm of 'greedy_search':
+
+    procedure greedy_search
+    input: remaining_tables
+    output: pplan;
+    {
+      pplan = <>;
+      do {
+        (t, a) = best_extension(pplan, remaining_tables);
+        pplan = concat(pplan, (t, a));
+        remaining_tables = remaining_tables - t;
+      } while (remaining_tables != {})
+      return pplan;
+    }
+
+    where 'best_extension' is a placeholder for a procedure that selects the
+    most "promising" of all tables in 'remaining_tables'.
+    Currently this estimate is performed by calling
+    'best_extension_by_limited_search' to evaluate all extensions of the
+    current QEP of size 'search_depth', thus the complexity of 'greedy_search'
+    mainly depends on that of 'best_extension_by_limited_search'.
+
+    If 'best_extension()' == 'best_extension_by_limited_search()', then the
+    worst-case complexity of this algorithm is <=
+    O(N*N^search_depth/search_depth). When serch_depth >= N, then the
+    complexity of greedy_search is O(N!).
+
+    In the future, 'greedy_search' might be extended to support other
+    implementations of 'best_extension', e.g. some simpler quadratic procedure.
+
+  RETURN
+    None
+*/
+
+static void
+greedy_search(JOIN      *join,
+              table_map remaining_tables,
+              uint      search_depth,
+              uint      heuristic)
+{
+  double    record_count= 1.0;
+  double    read_time=    0.0;
+  uint      idx= join->const_tables; // index into 'join->best_ref'
+  uint      best_idx;
+  uint      rem_size;    // cardinality of remaining_tables
+  POSITION  best_pos;
+  JOIN_TAB  *best_table; // the next plan node to be added to the curr QEP
+
+  DBUG_ENTER("greedy_search");
+
+  /* number of tables that remain to be optimized */
+  rem_size= my_count_bits(remaining_tables);
+
+  do {
+    /* Find the extension of the current QEP with the lowest cost */
+    join->best_read= DBL_MAX;
+    best_extension_by_limited_search(join, remaining_tables, idx, record_count,
+                                     read_time, search_depth, heuristic);
+
+    if (rem_size <= search_depth)
+    {
+      /*
+        'join->best_positions' contains a complete optimal extension of the
+        current partial QEP.
+      */
+      DBUG_EXECUTE("opt", print_plan(join, read_time, record_count,
+                                     join->tables, "optimal"););
+      DBUG_VOID_RETURN;
+    }
+
+    /* select the first table in the optimal extension as most promising */
+    best_pos= join->best_positions[idx];
+    best_table= best_pos.table;
+    /*
+      Each subsequent loop of 'best_extension_by_limited_search' uses
+      'join->positions' for cost estimates, therefore we have to update its
+      value.
+    */
+    join->positions[idx]= best_pos;
+
+    /* find the position of 'best_table' in 'join->best_ref' */
+    best_idx= idx;
+    JOIN_TAB *pos= join->best_ref[best_idx];
+    while (pos && best_table != pos)
+      pos= join->best_ref[++best_idx];
+    DBUG_ASSERT((pos != NULL)); // should always find 'best_table'
+    /* move 'best_table' at the first free position in the array of joins */
+    swap(JOIN_TAB*, join->best_ref[idx], join->best_ref[best_idx]);
+
+    /* compute the cost of the new plan extended with 'best_table' */
+    record_count*= join->positions[idx].records_read;
+    read_time+=    join->positions[idx].read_time;
+
+    remaining_tables&= ~(best_table->table->map);
+    --rem_size;
+    ++idx;
+
+    DBUG_EXECUTE("opt",
+                 print_plan(join, read_time, record_count, idx, "extended"););
+  } while (TRUE);
+}
+
+
+/*
+  Find a good, possibly optimal, query execution plan (QEP) by a possibly
+  exhaustive search.
+
+  SYNOPSIS
+    best_extension_by_limited_search()
+    join             pointer to the structure providing all context info for
+                     the query
+    remaining_tables set of tables not included into the partial plan yet
+    idx              length of the partial QEP in 'join->positions';
+                     since a depth-first search is used, also corresponds to
+                     the current depth of the search tree;
+                     also an index in the array 'join->best_ref';
+    record_count     estimate for the number of records returned by the best
+                     partial plan
+    read_time        the cost of the best partial plan
+    search_depth     maximum depth of the recursion and thus size of the found
+                     optimal plan (0 < search_depth <= join->tables+1).
+    heuristic        pruning heuristics that should be applied during optimization
+                     (values: 0 = EXHAUSTIVE, 1 = PRUNE_BY_TIME_OR_ROWS)
+
+  DESCRIPTION
+    The procedure searches for the optimal ordering of the query tables in set
+    'remaining_tables' of size N, and the corresponding optimal access paths to each
+    table. The choice of a table order and an access path for each table
+    constitutes a query execution plan (QEP) that fully specifies how to
+    execute the query.
+   
+    The maximal size of the found plan is controlled by the parameter
+    'search_depth'. When search_depth == N, the resulting plan is complete and
+    can be used directly as a QEP. If search_depth < N, the found plan consists
+    of only some of the query tables. Such "partial" optimal plans are useful
+    only as input to query optimization procedures, and cannot be used directly
+    to execute a query.
+
+    The algorithm begins with an empty partial plan stored in 'join->positions'
+    and a set of N tables - 'remaining_tables'. Each step of the algorithm
+    evaluates the cost of the partial plan extended by all access plans for
+    each of the relations in 'remaining_tables', expands the current partial
+    plan with the access plan that results in lowest cost of the expanded
+    partial plan, and removes the corresponding relation from
+    'remaining_tables'. The algorithm continues until it either constructs a
+    complete optimal plan, or constructs an optimal plartial plan with size =
+    search_depth.
+
+    The final optimal plan is stored in 'join->best_positions'. The
+    corresponding cost of the optimal plan is in 'join->best_read'.
+
+  NOTES
+    The procedure uses a recursive depth-first search where the depth of the
+    recursion (and thus the exhaustiveness of the search) is controlled by the
+    parameter 'search_depth'.
+
+    The pseudocode below describes the algorithm of
+    'best_extension_by_limited_search'. The worst-case complexity of this
+    algorithm is O(N*N^search_depth/search_depth). When serch_depth >= N, then
+    the complexity of greedy_search is O(N!).
+
+    procedure best_extension_by_limited_search(
+      pplan in,             // in, partial plan of tables-joined-so-far
+      pplan_cost,           // in, cost of pplan
+      remaining_tables,     // in, set of tables not referenced in pplan
+      best_plan_so_far,     // in/out, best plan found so far
+      best_plan_so_far_cost,// in/out, cost of best_plan_so_far
+      search_depth)         // in, maximum size of the plans being considered
+    {
+      for each table T from remaining_tables
+      {
+        // Calculate the cost of using table T as above
+        cost = complex-series-of-calculations;
+
+        // Add the cost to the cost so far.
+        pplan_cost+= cost;
+
+        if (pplan_cost >= best_plan_so_far_cost)
+          // pplan_cost already too great, stop search
+          continue;
+
+        pplan= expand pplan by best_access_method;
+        remaining_tables= remaining_tables - table T;
+        if (remaining_tables is not an empty set
+            and
+            search_depth > 1)
+        {
+          best_extension_by_limited_search(pplan, pplan_cost,
+                                           remaining_tables,
+                                           best_plan_so_far,
+                                           best_plan_so_far_cost,
+                                           search_depth - 1);
+        }
+        else
+        {
+          best_plan_so_far_cost= pplan_cost;
+          best_plan_so_far= pplan;
+        }
+      }
+    }
+
+  IMPLEMENTATION
+    When 'best_extension_by_limited_search' is called for the first time,
+    'join->best_read' must be set to the largest possible value (e.g. DBL_MAX).
+    The actual implementation provides a way to optionally use pruning
+    heuristics (controlled by the parameter 'heuristic') to reduce the search
+    space by skipping some partial plans.
+    The parameter 'search_depth' provides control over the recursion
+    depth, and thus the size of the resulting optimal plan.
+
+  RETURN
+    None
+*/
+
+static void
+best_extension_by_limited_search(JOIN      *join,
+                                 table_map remaining_tables,
+                                 uint      idx,
+                                 double    record_count,
+                                 double    read_time,
+                                 uint      search_depth,
+                                 uint      heuristic)
+{
+  THD *thd= join->thd;
+  if (thd->killed)  // Abort
+    return;
+
+  DBUG_ENTER("best_extension_by_limited_search");
+
+  /* 
+     'join' is a partial plan with lower cost than the best plan so far,
+     so continue expanding it further with the tables in 'remaining_tables'.
+  */
+  JOIN_TAB *s;
+  double best_record_count= DBL_MAX;
+  double best_read_time=    DBL_MAX;
+
+  DBUG_EXECUTE("opt",
+               print_plan(join, read_time, record_count, idx, "part_plan"););
+
+  for (JOIN_TAB **pos= join->best_ref + idx ; (s= *pos) ; pos++)
+  {
+    table_map real_table_bit= s->table->map;
+    if ((remaining_tables & real_table_bit) && !(remaining_tables & s->dependent))
+    {
+      double current_record_count, current_read_time;
+
+      /* Find the best access method from 's' to the current partial plan */
+      best_access_path(join, s, thd, remaining_tables, idx, record_count, read_time);
+      /* Compute the cost of extending the plan with 's' */
+      current_record_count= record_count * join->positions[idx].records_read;
+      current_read_time=    read_time + join->positions[idx].read_time;
+
+      /* Expand only partial plans with lower cost than the best QEP so far */
+      if ((current_read_time +
+           current_record_count / (double) TIME_FOR_COMPARE) >= join->best_read)
+      {
+        DBUG_EXECUTE("opt", print_plan(join, read_time, record_count, idx,
+                                       "prune_by_cost"););
+        continue;
+      }
+
+      /*
+        Prune some less promising partial plans. This heuristic may miss
+        the optimal QEPs, thus it results in a non-exhaustive search.
+      */
+      if (heuristic == 1)
+      {
+        if (best_record_count > current_record_count ||
+            best_read_time > current_read_time ||
+            idx == join->const_tables &&  // 's' is the first table in the QEP
+            s->table == join->sort_by_table)
+        {
+          if (best_record_count >= current_record_count &&
+              best_read_time >= current_read_time &&
+              /* TODO: What is the reasoning behind this condition? */
+              (!(s->key_dependent & remaining_tables) ||
+               join->positions[idx].records_read < 2.0))
+          {
+            best_record_count= current_record_count;
+            best_read_time=    current_read_time;
+          }
+        }
+        else
+        {
+          DBUG_EXECUTE("opt", print_plan(join, read_time, record_count, idx,
+                                         "prune_by_heuristic"););
+          continue;
+        }
+      }
+
+      if ( (search_depth > 1) && (remaining_tables & ~real_table_bit) )
+      { /* Recursively expand the current partial plan */
+        swap(JOIN_TAB*, join->best_ref[idx], *pos);
+        best_extension_by_limited_search(join,
+                                         remaining_tables & ~real_table_bit,
+                                         idx + 1,
+                                         current_record_count,
+                                         current_read_time,
+                                         search_depth - 1,
+                                         heuristic);
+        if (thd->killed)
+          DBUG_VOID_RETURN;
+        swap(JOIN_TAB*, join->best_ref[idx], *pos);
+      }
+      else
+      { /*
+          'join' is either the best partial QEP with 'search_depth' relations,
+          or the best complete QEP so far, whichever is smaller.
+        */
+        current_read_time+= current_record_count / (double) TIME_FOR_COMPARE;
+        if (join->sort_by_table &&
+            join->sort_by_table != join->positions[join->const_tables].table->table)
+          /* We have to make a temp table */
+          current_read_time+= current_record_count;
+        if ((search_depth == 1) || (current_read_time < join->best_read))
+        {
+          memcpy((gptr) join->best_positions, (gptr) join->positions,
+                 sizeof(POSITION) * (idx + 1));
+          join->best_read= current_read_time;
+        }
+        DBUG_EXECUTE("opt",
+                     print_plan(join, current_read_time, current_record_count, idx, "full_plan"););
+      }
+    }
+  }
+  DBUG_VOID_RETURN;
+}
+
+
+/*
+  TODO: this function is here only temporarily until 'greedy_search' is
+  tested and accepted.
+*/
 static void
 find_best(JOIN *join,table_map rest_tables,uint idx,double record_count,
 	  double read_time)

sql/sql_select.h

@@ -116,6 +116,7 @@ typedef struct st_join_table {
 typedef struct st_position			/* Used in find_best */
 {
   double records_read;
+  double read_time;
   JOIN_TAB *table;
   KEYUSE *key;
 } POSITION;
@@ -133,8 +134,9 @@ typedef struct st_rollup
 class JOIN :public Sql_alloc
 {
  public:
-  JOIN_TAB *join_tab,**best_ref,**map2table;
+  JOIN_TAB *join_tab,**best_ref;
-  JOIN_TAB *join_tab_save; //saved join_tab for subquery reexecution
+  JOIN_TAB **map2table;    // mapping between table indexes and JOIN_TABs
+  JOIN_TAB *join_tab_save; // saved join_tab for subquery reexecution
   TABLE    **table,**all_tables,*sort_by_table;
   uint	   tables,const_tables;
   uint	   send_group_parts;

sql/sql_show.cc

@@ -1845,6 +1845,11 @@ int mysqld_show(THD *thd, const char *wild, show_var_st *variables,
         end= strend(pos);
         break;
       }
+      case SHOW_DOUBLE:
+      {
+        end= buff + sprintf(buff, "%f", *(double*) value);
+        break;
+      }
 #ifdef HAVE_OPENSSL
 	/* First group - functions relying on CTX */
       case SHOW_SSL_CTX_SESS_ACCEPT:

sql/sql_test.cc

@@ -232,6 +232,102 @@ TEST_join(JOIN *join)
   DBUG_VOID_RETURN;
 }
 
+
+/* 
+  Print the current state during query optimization.
+
+  SYNOPSIS
+    print_plan()
+    join         pointer to the structure providing all context info for
+                 the query
+    read_time    the cost of the best partial plan
+    record_count estimate for the number of records returned by the best
+                 partial plan
+    idx          length of the partial QEP in 'join->positions';
+                 also an index in the array 'join->best_ref';
+    info         comment string to appear above the printout
+
+  DESCRIPTION
+    This function prints to the log file DBUG_FILE the members of 'join' that
+    are used during query optimization (join->positions, join->best_positions,
+    and join->best_ref) and few other related variables (read_time,
+    record_count).
+    Useful to trace query optimizer functions.
+
+  RETURN
+    None
+*/
+
+void
+print_plan(JOIN* join, double read_time, double record_count,
+           uint idx, const char *info)
+{
+  uint i;
+  POSITION pos;
+  JOIN_TAB *join_table;
+  JOIN_TAB **plan_nodes;
+  TABLE*   table;
+
+  if (info == 0)
+    info= "";
+
+  DBUG_LOCK_FILE;
+  if (join->best_read == DBL_MAX)
+  {
+    fprintf(DBUG_FILE,"%s; idx:%u, best: DBL_MAX, current:%g\n",
+            info, idx, read_time);
+  }
+  else
+  {
+    fprintf(DBUG_FILE,"%s; idx: %u, best: %g, current: %g\n",
+            info, idx, join->best_read, read_time);
+  }
+
+  /* Print the tables in JOIN->positions */
+  fputs("     POSITIONS: ", DBUG_FILE);
+  for (i= 0; i < idx ; i++)
+  {
+    pos = join->positions[i];
+    table= pos.table->table;
+    if (table)
+      fputs(table->real_name, DBUG_FILE);
+    fputc(' ', DBUG_FILE);
+  }
+  fputc('\n', DBUG_FILE);
+
+  /*
+    Print the tables in JOIN->best_positions only if at least one complete plan
+    has been found. An indicator for this is the value of 'join->best_read'.
+  */
+  fputs("BEST_POSITIONS: ", DBUG_FILE);
+  if (join->best_read < DBL_MAX)
+  {
+    for (i= 0; i < idx ; i++)
+    {
+      pos= join->best_positions[i];
+      table= pos.table->table;
+      if (table)
+        fputs(table->real_name, DBUG_FILE);
+      fputc(' ', DBUG_FILE);
+    }
+  }
+  fputc('\n', DBUG_FILE);
+
+  /* Print the tables in JOIN->best_ref */
+  fputs("      BEST_REF: ", DBUG_FILE);
+  for (plan_nodes= join->best_ref ; *plan_nodes ; plan_nodes++)
+  {
+    join_table= (*plan_nodes);
+    fputs(join_table->table->real_name, DBUG_FILE);
+    fprintf(DBUG_FILE, "(%u,%u,%u)",
+            join_table->found_records, join_table->records, join_table->read_time);
+    fputc(' ', DBUG_FILE);
+  }
+  fputc('\n', DBUG_FILE);
+
+  DBUG_UNLOCK_FILE;
+}
+
 #endif
 
 typedef struct st_debug_lock

sql/structs.h

@@ -167,8 +167,8 @@ typedef struct st_known_date_time_format {
 enum SHOW_TYPE
 {
   SHOW_UNDEF,
-  SHOW_LONG, SHOW_LONGLONG, SHOW_INT, SHOW_CHAR, SHOW_CHAR_PTR, SHOW_BOOL,
+  SHOW_LONG, SHOW_LONGLONG, SHOW_INT, SHOW_CHAR, SHOW_CHAR_PTR, SHOW_DOUBLE,
-  SHOW_MY_BOOL, SHOW_OPENTABLES, SHOW_STARTTIME, SHOW_QUESTION,
+  SHOW_BOOL, SHOW_MY_BOOL, SHOW_OPENTABLES, SHOW_STARTTIME, SHOW_QUESTION,
   SHOW_LONG_CONST, SHOW_INT_CONST, SHOW_HAVE, SHOW_SYS, SHOW_HA_ROWS,
 #ifdef HAVE_OPENSSL
   SHOW_SSL_CTX_SESS_ACCEPT, 	SHOW_SSL_CTX_SESS_ACCEPT_GOOD,