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Merge.

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This commit is contained in:
Igor Babaev
2011-09-08 09:21:31 -07:00
parent 3e97aeafd6 be03fe9c29
commit 5746b96825
5 changed files with 260 additions and 26 deletions
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158
mysql-test/r/derived_view.result
View File

@@ -704,8 +704,8 @@ SELECT t.a FROM t1 LEFT JOIN
GROUP BY t.a; GROUP BY t.a;
id select_type table type possible_keys key key_len ref rows filtered Extra id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Using temporary; Using filesort 1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Using temporary; Using filesort
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where 1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where
Warnings: Warnings:
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t1` left join (`test`.`t2` join `test`.`t3`) on(((`test`.`t2`.`a` >= 1) and (`test`.`t3`.`b` > 5))) where 1 group by `test`.`t2`.`a` Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t1` left join (`test`.`t2` join `test`.`t3`) on(((`test`.`t2`.`a` >= 1) and (`test`.`t3`.`b` > 5))) where 1 group by `test`.`t2`.`a`
SELECT t.a FROM t1 LEFT JOIN SELECT t.a FROM t1 LEFT JOIN
@@ -720,8 +720,8 @@ SELECT t.a FROM t1 LEFT JOIN
GROUP BY t.a; GROUP BY t.a;
id select_type table type possible_keys key key_len ref rows filtered Extra id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Using temporary; Using filesort 1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00 Using temporary; Using filesort
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where 1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where
Warnings: Warnings:
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t1` left join (`test`.`t2` join `test`.`t3`) on(((`test`.`t2`.`a` >= 1) and (`test`.`t3`.`b` > 5))) where 1 group by `test`.`t2`.`a` Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t1` left join (`test`.`t2` join `test`.`t3`) on(((`test`.`t2`.`a` >= 1) and (`test`.`t3`.`b` > 5))) where 1 group by `test`.`t2`.`a`
SELECT t.a FROM t1 LEFT JOIN SELECT t.a FROM t1 LEFT JOIN
@@ -1084,8 +1084,8 @@ EXPLAIN EXTENDED
SELECT t.a,t.b FROM t3 RIGHT JOIN ((SELECT * FROM t1) AS t, t2) ON t2.b != 0 SELECT t.a,t.b FROM t3 RIGHT JOIN ((SELECT * FROM t1) AS t, t2) ON t2.b != 0
WHERE (t.a,t.b) NOT IN (SELECT 7, 5); WHERE (t.a,t.b) NOT IN (SELECT 7, 5);
id select_type table type possible_keys key key_len ref rows filtered Extra id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 system NULL NULL NULL NULL 1 100.00
1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00 1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00
1 PRIMARY t2 system NULL NULL NULL NULL 1 100.00
1 PRIMARY t3 system NULL NULL NULL NULL 1 100.00 1 PRIMARY t3 system NULL NULL NULL NULL 1 100.00
3 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL No tables used 3 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings: Warnings:
@@ -1098,8 +1098,8 @@ EXPLAIN EXTENDED
SELECT t.a,t.b FROM t3 RIGHT JOIN (v1 AS t, t2) ON t2.b != 0 SELECT t.a,t.b FROM t3 RIGHT JOIN (v1 AS t, t2) ON t2.b != 0
WHERE (t.a,t.b) NOT IN (SELECT 7, 5); WHERE (t.a,t.b) NOT IN (SELECT 7, 5);
id select_type table type possible_keys key key_len ref rows filtered Extra id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 system NULL NULL NULL NULL 1 100.00
1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00 1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00
1 PRIMARY t2 system NULL NULL NULL NULL 1 100.00
1 PRIMARY t3 system NULL NULL NULL NULL 1 100.00 1 PRIMARY t3 system NULL NULL NULL NULL 1 100.00
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL No tables used 2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings: Warnings:
@@ -1270,4 +1270,154 @@ a
r r
p p
DROP TABLE t1,t2,t3; DROP TABLE t1,t2,t3;
#
# LP bug #824463: nested outer join using a merged view
# as an inner table
#
CREATE TABLE t1 (b int, a int) ;
CREATE TABLE t2 (a int) ;
INSERT INTO t2 VALUES (5), (6);
CREATE TABLE t3 (a int , c int) ;
INSERT INTO t3 VALUES (22,1), (23,-1);
CREATE TABLE t4 (a int);
CREATE TABLE t5 (d int) ;
INSERT INTO t5 VALUES (0), (7), (3), (5);
CREATE VIEW v2 AS SELECT * FROM t2;
CREATE VIEW v3 AS SELECT * FROM t3;
EXPLAIN EXTENDED
SELECT STRAIGHT_JOIN *
FROM ( t2 AS s2
JOIN
( t3 AS s3
LEFT JOIN
( t4 LEFT JOIN t3 ON t4.a != 0 )
ON s3.a != 0)
ON s2.a != 0)
JOIN t5 ON s3.c != 0 AND t5.d = 0;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE s2 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE s3 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t4 ALL NULL NULL NULL NULL 0 0.00 Using where
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t5 ALL NULL NULL NULL NULL 4 100.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select straight_join `test`.`s2`.`a` AS `a`,`test`.`s3`.`a` AS `a`,`test`.`s3`.`c` AS `c`,`test`.`t4`.`a` AS `a`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`c` AS `c`,`test`.`t5`.`d` AS `d` from `test`.`t2` `s2` join `test`.`t3` `s3` left join (`test`.`t4` left join `test`.`t3` on((`test`.`t4`.`a` <> 0))) on((`test`.`s3`.`a` <> 0)) join `test`.`t5` where ((`test`.`t5`.`d` = 0) and (`test`.`s3`.`c` <> 0) and (`test`.`s2`.`a` <> 0))
SELECT STRAIGHT_JOIN *
FROM ( t2 AS s2
JOIN
( t3 AS s3
LEFT JOIN
( t4 LEFT JOIN t3 ON t4.a != 0 )
ON s3.a != 0)
ON s2.a != 0)
JOIN t5 ON s3.c != 0 AND t5.d = 0;
a a c a a c d
5 22 1 NULL NULL NULL 0
6 22 1 NULL NULL NULL 0
5 23 -1 NULL NULL NULL 0
6 23 -1 NULL NULL NULL 0
EXPLAIN EXTENDED
SELECT STRAIGHT_JOIN *
FROM t2 AS s2 , t5,
(t3 LEFT JOIN (t4 LEFT JOIN t3 AS s3 ON t4.a != 0) ON t3.a != 0)
WHERE s2.a != 0 AND t3.c != 0 AND t5.d = 0;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE s2 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t5 ALL NULL NULL NULL NULL 4 100.00 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t4 ALL NULL NULL NULL NULL 0 0.00 Using where
1 SIMPLE s3 ALL NULL NULL NULL NULL 2 100.00 Using where
Warnings:
Note 1003 select straight_join `test`.`s2`.`a` AS `a`,`test`.`t5`.`d` AS `d`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`c` AS `c`,`test`.`t4`.`a` AS `a`,`test`.`s3`.`a` AS `a`,`test`.`s3`.`c` AS `c` from `test`.`t2` `s2` join `test`.`t5` join `test`.`t3` left join (`test`.`t4` left join `test`.`t3` `s3` on((`test`.`t4`.`a` <> 0))) on((`test`.`t3`.`a` <> 0)) where ((`test`.`t5`.`d` = 0) and (`test`.`s2`.`a` <> 0) and (`test`.`t3`.`c` <> 0))
SELECT STRAIGHT_JOIN *
FROM t2 AS s2 , t5,
(t3 LEFT JOIN (t4 LEFT JOIN t3 AS s3 ON t4.a != 0) ON t3.a != 0)
WHERE s2.a != 0 AND t3.c != 0 AND t5.d = 0;
a d a c a a c
5 0 22 1 NULL NULL NULL
6 0 22 1 NULL NULL NULL
5 0 23 -1 NULL NULL NULL
6 0 23 -1 NULL NULL NULL
EXPLAIN EXTENDED
SELECT STRAIGHT_JOIN *
FROM v2 AS s2 , t5,
(t3 LEFT JOIN (t4 LEFT JOIN v3 AS s3 ON t4.a != 0) ON t3.a != 0)
WHERE s2.a != 0 AND t3.c != 0 AND t5.d = 0;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t5 ALL NULL NULL NULL NULL 4 100.00 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t4 ALL NULL NULL NULL NULL 0 0.00 Using where
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where
Warnings:
Note 1003 select straight_join `test`.`t2`.`a` AS `a`,`test`.`t5`.`d` AS `d`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`c` AS `c`,`test`.`t4`.`a` AS `a`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`c` AS `c` from `test`.`t2` join `test`.`t5` join `test`.`t3` left join (`test`.`t4` left join (`test`.`t3`) on((`test`.`t4`.`a` <> 0))) on((`test`.`t3`.`a` <> 0)) where ((`test`.`t5`.`d` = 0) and (`test`.`t2`.`a` <> 0) and (`test`.`t3`.`c` <> 0))
SELECT STRAIGHT_JOIN *
FROM v2 AS s2 , t5,
(t3 LEFT JOIN (t4 LEFT JOIN v3 AS s3 ON t4.a != 0) ON t3.a != 0)
WHERE s2.a != 0 AND t3.c != 0 AND t5.d = 0;
a d a c a a c
5 0 22 1 NULL NULL NULL
6 0 22 1 NULL NULL NULL
5 0 23 -1 NULL NULL NULL
6 0 23 -1 NULL NULL NULL
SELECT STRAIGHT_JOIN *
FROM ( ( t2 AS s2
LEFT JOIN
( t3 AS s3
LEFT JOIN
( t4 AS s4 JOIN t3 ON s4.a != 0)
ON s3.a != 0 )
ON s2.a != 0)
LEFT JOIN
t1 AS s1
ON s1.a != 0)
JOIN t5 ON s3.c != 0;
a a c a a c b a d
5 22 1 NULL NULL NULL NULL NULL 0
6 22 1 NULL NULL NULL NULL NULL 0
5 23 -1 NULL NULL NULL NULL NULL 0
6 23 -1 NULL NULL NULL NULL NULL 0
5 22 1 NULL NULL NULL NULL NULL 7
6 22 1 NULL NULL NULL NULL NULL 7
5 23 -1 NULL NULL NULL NULL NULL 7
6 23 -1 NULL NULL NULL NULL NULL 7
5 22 1 NULL NULL NULL NULL NULL 3
6 22 1 NULL NULL NULL NULL NULL 3
5 23 -1 NULL NULL NULL NULL NULL 3
6 23 -1 NULL NULL NULL NULL NULL 3
5 22 1 NULL NULL NULL NULL NULL 5
6 22 1 NULL NULL NULL NULL NULL 5
5 23 -1 NULL NULL NULL NULL NULL 5
6 23 -1 NULL NULL NULL NULL NULL 5
SELECT STRAIGHT_JOIN *
FROM ( ( v2 AS s2
LEFT JOIN
( v3 AS s3
LEFT JOIN
( t4 AS s4 JOIN v3 ON s4.a != 0)
ON s3.a != 0 )
ON s2.a != 0)
LEFT JOIN
t1 AS s1
ON s1.a != 0)
JOIN t5 ON s3.c != 0;
a a c a a c b a d
5 22 1 NULL NULL NULL NULL NULL 0
6 22 1 NULL NULL NULL NULL NULL 0
5 23 -1 NULL NULL NULL NULL NULL 0
6 23 -1 NULL NULL NULL NULL NULL 0
5 22 1 NULL NULL NULL NULL NULL 7
6 22 1 NULL NULL NULL NULL NULL 7
5 23 -1 NULL NULL NULL NULL NULL 7
6 23 -1 NULL NULL NULL NULL NULL 7
5 22 1 NULL NULL NULL NULL NULL 3
6 22 1 NULL NULL NULL NULL NULL 3
5 23 -1 NULL NULL NULL NULL NULL 3
6 23 -1 NULL NULL NULL NULL NULL 3
5 22 1 NULL NULL NULL NULL NULL 5
6 22 1 NULL NULL NULL NULL NULL 5
5 23 -1 NULL NULL NULL NULL NULL 5
6 23 -1 NULL NULL NULL NULL NULL 5
DROP VIEW v2,v3;
DROP TABLE t1,t2,t3,t4,t5;
set optimizer_switch=@exit_optimizer_switch; set optimizer_switch=@exit_optimizer_switch;

12
mysql-test/r/ps_ddl.result
View File

@@ -1508,12 +1508,12 @@ create view v_27690_1 as select A.a, A.b from t_27690_1 A, t_27690_1 B;
execute stmt; execute stmt;
a b a b a b a b
1 1 1 1 1 1 1 1
1 1 2 2
2 2 1 1 2 2 1 1
2 2 2 2
1 1 1 1 1 1 1 1
1 1 2 2
2 2 1 1 2 2 1 1
1 1 2 2
2 2 2 2
1 1 2 2
2 2 2 2 2 2 2 2
call p_verify_reprepare_count(1); call p_verify_reprepare_count(1);
SUCCESS SUCCESS
@@ -1521,12 +1521,12 @@ SUCCESS
execute stmt; execute stmt;
a b a b a b a b
1 1 1 1 1 1 1 1
1 1 2 2
2 2 1 1 2 2 1 1
2 2 2 2
1 1 1 1 1 1 1 1
1 1 2 2
2 2 1 1 2 2 1 1
1 1 2 2
2 2 2 2
1 1 2 2
2 2 2 2 2 2 2 2
call p_verify_reprepare_count(0); call p_verify_reprepare_count(0);
SUCCESS SUCCESS

89
mysql-test/t/derived_view.test
View File

@@ -783,5 +783,94 @@ WHERE EXISTS (SELECT t2.a FROM t3 RIGHT JOIN t2 ON (t3.a = t2.a)
DROP TABLE t1,t2,t3; DROP TABLE t1,t2,t3;
--echo #
--echo # LP bug #824463: nested outer join using a merged view
--echo # as an inner table
--echo #
CREATE TABLE t1 (b int, a int) ;
CREATE TABLE t2 (a int) ;
INSERT INTO t2 VALUES (5), (6);
CREATE TABLE t3 (a int , c int) ;
INSERT INTO t3 VALUES (22,1), (23,-1);
CREATE TABLE t4 (a int);
CREATE TABLE t5 (d int) ;
INSERT INTO t5 VALUES (0), (7), (3), (5);
CREATE VIEW v2 AS SELECT * FROM t2;
CREATE VIEW v3 AS SELECT * FROM t3;
EXPLAIN EXTENDED
SELECT STRAIGHT_JOIN *
FROM ( t2 AS s2
JOIN
( t3 AS s3
LEFT JOIN
( t4 LEFT JOIN t3 ON t4.a != 0 )
ON s3.a != 0)
ON s2.a != 0)
JOIN t5 ON s3.c != 0 AND t5.d = 0;
SELECT STRAIGHT_JOIN *
FROM ( t2 AS s2
JOIN
( t3 AS s3
LEFT JOIN
( t4 LEFT JOIN t3 ON t4.a != 0 )
ON s3.a != 0)
ON s2.a != 0)
JOIN t5 ON s3.c != 0 AND t5.d = 0;
EXPLAIN EXTENDED
SELECT STRAIGHT_JOIN *
FROM t2 AS s2 , t5,
(t3 LEFT JOIN (t4 LEFT JOIN t3 AS s3 ON t4.a != 0) ON t3.a != 0)
WHERE s2.a != 0 AND t3.c != 0 AND t5.d = 0;
SELECT STRAIGHT_JOIN *
FROM t2 AS s2 , t5,
(t3 LEFT JOIN (t4 LEFT JOIN t3 AS s3 ON t4.a != 0) ON t3.a != 0)
WHERE s2.a != 0 AND t3.c != 0 AND t5.d = 0;
EXPLAIN EXTENDED
SELECT STRAIGHT_JOIN *
FROM v2 AS s2 , t5,
(t3 LEFT JOIN (t4 LEFT JOIN v3 AS s3 ON t4.a != 0) ON t3.a != 0)
WHERE s2.a != 0 AND t3.c != 0 AND t5.d = 0;
SELECT STRAIGHT_JOIN *
FROM v2 AS s2 , t5,
(t3 LEFT JOIN (t4 LEFT JOIN v3 AS s3 ON t4.a != 0) ON t3.a != 0)
WHERE s2.a != 0 AND t3.c != 0 AND t5.d = 0;
SELECT STRAIGHT_JOIN *
FROM ( ( t2 AS s2
LEFT JOIN
( t3 AS s3
LEFT JOIN
( t4 AS s4 JOIN t3 ON s4.a != 0)
ON s3.a != 0 )
ON s2.a != 0)
LEFT JOIN
t1 AS s1
ON s1.a != 0)
JOIN t5 ON s3.c != 0;
SELECT STRAIGHT_JOIN *
FROM ( ( v2 AS s2
LEFT JOIN
( v3 AS s3
LEFT JOIN
( t4 AS s4 JOIN v3 ON s4.a != 0)
ON s3.a != 0 )
ON s2.a != 0)
LEFT JOIN
t1 AS s1
ON s1.a != 0)
JOIN t5 ON s3.c != 0;
DROP VIEW v2,v3;
DROP TABLE t1,t2,t3,t4,t5;
# The following command must be the last one the file # The following command must be the last one the file
set optimizer_switch=@exit_optimizer_switch; set optimizer_switch=@exit_optimizer_switch;

25
sql/sql_lex.cc
View File

@@ -3220,18 +3220,19 @@ void st_select_lex::append_table_to_list(TABLE_LIST *TABLE_LIST::*link,
tl->*link= table; tl->*link= table;
} }
/* /*
@brief @brief
Remove given table from the leaf_tables list. Replace given table from the leaf_tables list for a list of tables
@param link Offset to which list in table structure to use @param table Table to replace
@param table Table to remove @param list List to substititute the table for
@details @details
Remove 'table' from the leaf_tables list using the 'link' offset. Replace 'table' from the leaf_tables list for a list of tables 'tbl_list'.
*/ */
void st_select_lex::remove_table_from_list(TABLE_LIST *table) void st_select_lex::replace_leaf_table(TABLE_LIST *table, List<TABLE_LIST> &tbl_list)
{ {
TABLE_LIST *tl; TABLE_LIST *tl;
List_iterator<TABLE_LIST> ti(leaf_tables); List_iterator<TABLE_LIST> ti(leaf_tables);
@@ -3239,7 +3240,7 @@ void st_select_lex::remove_table_from_list(TABLE_LIST *table)
{ {
if (tl == table) if (tl == table)
{ {
ti.remove(); ti.replace(tbl_list);
break; break;
} }
} }
@@ -3344,8 +3345,6 @@ bool SELECT_LEX::merge_subquery(THD *thd, TABLE_LIST *derived,
uint table_no, table_map map) uint table_no, table_map map)
{ {
derived->wrap_into_nested_join(subq_select->top_join_list); derived->wrap_into_nested_join(subq_select->top_join_list);
/* Reconnect the next_leaf chain. */
leaf_tables.concat(&subq_select->leaf_tables);
ftfunc_list->concat(subq_select->ftfunc_list); ftfunc_list->concat(subq_select->ftfunc_list);
if (join || if (join ||
@@ -3361,18 +3360,14 @@ bool SELECT_LEX::merge_subquery(THD *thd, TABLE_LIST *derived,
in_subq->emb_on_expr_nest= derived; in_subq->emb_on_expr_nest= derived;
} }
} }
/*
Remove merged table from chain.
When merge_subquery is called at a subquery-to-semijoin transformation
the derived isn't in the leaf_tables list, so in this case the call of
remove_table_from_list does not cause any actions.
*/
remove_table_from_list(derived);
/* Walk through child's tables and adjust table map, tablenr, /* Walk through child's tables and adjust table map, tablenr,
* parent_lex */ * parent_lex */
subq_select->remap_tables(derived, map, table_no, this); subq_select->remap_tables(derived, map, table_no, this);
subq_select->merged_into= this; subq_select->merged_into= this;
replace_leaf_table(derived, subq_select->leaf_tables);
return FALSE; return FALSE;
} }

2
sql/sql_lex.h
View File

@@ -888,7 +888,7 @@ public:
bool handle_derived(struct st_lex *lex, uint phases); bool handle_derived(struct st_lex *lex, uint phases);
void append_table_to_list(TABLE_LIST *TABLE_LIST::*link, TABLE_LIST *table); void append_table_to_list(TABLE_LIST *TABLE_LIST::*link, TABLE_LIST *table);
bool get_free_table_map(table_map *map, uint *tablenr); bool get_free_table_map(table_map *map, uint *tablenr);
void remove_table_from_list(TABLE_LIST *table); void replace_leaf_table(TABLE_LIST *table, List<TABLE_LIST> &tbl_list);
void remap_tables(TABLE_LIST *derived, table_map map, void remap_tables(TABLE_LIST *derived, table_map map,
uint tablenr, st_select_lex *parent_lex); uint tablenr, st_select_lex *parent_lex);
bool merge_subquery(THD *thd, TABLE_LIST *derived, st_select_lex *subq_lex, bool merge_subquery(THD *thd, TABLE_LIST *derived, st_select_lex *subq_lex,