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	can be specified
Currently MySQL allows one to specify what indexes to ignore during
join optimization. The scope of the current USE/FORCE/IGNORE INDEX 
statement is only the FROM clause, while all other clauses are not 
affected.
However, in certain cases, the optimizer
may incorrectly choose an index for sorting and/or grouping, and
produce an inefficient query plan.
This task provides the means to specify what indexes are
ignored/used for what operation in a more fine-grained manner, thus
making it possible to manually force a better plan. We do this
by extending the current IGNORE/USE/FORCE INDEX syntax to:
IGNORE/USE/FORCE INDEX [FOR {JOIN | ORDER | GROUP BY}]
so that:
- if no FOR is specified, the index hint will apply everywhere.
- if MySQL is started with the compatibility option --old_mode then
  an index hint without a FOR clause works as in 5.0 (i.e, the 
  index will only be ignored for JOINs, but can still be used to
  compute ORDER BY).
See the WL#3527 for further details.
BitKeeper/deleted/.del-mysqld.cc.rej:
  Rename: sql/mysqld.cc.rej -> BitKeeper/deleted/.del-mysqld.cc.rej
BitKeeper/deleted/.del-sql_parse.cc.rej:
  Rename: sql/sql_parse.cc.rej -> BitKeeper/deleted/.del-sql_parse.cc.rej
BitKeeper/deleted/.del-table.cc.rej:
  Rename: sql/table.cc.rej -> BitKeeper/deleted/.del-table.cc.rej
mysql-test/r/endspace.result:
  WL3527 : fixed undeterministic test
mysql-test/r/group_by.result:
  WL#3527: test cases
mysql-test/t/endspace.test:
  WL3527 : fixed undeterministic test
mysql-test/t/group_by.test:
  WL#3527: test cases
sql/item.cc:
  WL#3527: renames
sql/mysql_priv.h:
  WL#3527: corrected initialization
sql/mysqld.cc:
  WL#3527: added old_mode command line option
sql/opt_range.cc:
  WL#3527: renames
sql/sql_base.cc:
  WL#3527: 
   - renames
   - correct initialization
   - extended the processing of USE/FORCE/IGNORE index
sql/sql_class.h:
  WL#3527: added old_mode command line option
sql/sql_delete.cc:
  WL#3527: renames
sql/sql_help.cc:
  WL#3527: renames
sql/sql_lex.cc:
  WL#3527: extended parsing of USE/FORCE/IGNORE index
sql/sql_lex.h:
  WL#3527: extended parsing of USE/FORCE/IGNORE index
sql/sql_parse.cc:
  WL#3527: extended parsing of USE/FORCE/IGNORE index
sql/sql_select.cc:
  WL#3527:
   - renames
   - passing additional info to support the extended 
     USE/FORCE/IGNORE INDEX syntax
   - If there is a covering index, and we have 
     IGNORE INDEX FOR GROUP/ORDER, and this index is 
     used for the JOIN part, then we have to ignore the
     IGNORE INDEX FOR GROUP/ORDER.
sql/sql_show.cc:
  WL#3527: passing additional info to support the extended 
     USE/FORCE/IGNORE INDEX syntax
sql/sql_update.cc:
  WL#3527: renames
sql/sql_yacc.yy:
  WL#3527: extended parsing of USE/FORCE/IGNORE index
sql/table.cc:
  WL#3527: extended the processing of USE/FORCE/IGNORE index
sql/table.h:
  WL#3527: extended the processing of USE/FORCE/IGNORE index
storage/myisam/ha_myisam.cc:
  WL#3527: extended the processing of USE/FORCE/IGNORE index
		
	
		
			
				
	
	
		
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| #
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| # Test problem with characters < ' ' at end of strings (Bug #3152)
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| #
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| 
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| -- source include/have_innodb.inc
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| --disable_warnings
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| drop table if exists t1;
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| --enable_warnings
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| 
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| -- source include/endspace.inc
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| 
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| #
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| # Test MyISAM tables.
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| #
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| 
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| create table t1 (text1 varchar(32) not NULL, KEY key1 (text1));
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| insert into t1 values ('teststring'), ('nothing'), ('teststring\t');
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| check table t1;
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| select * from t1 ignore key (key1) where text1='teststring' or 
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|   text1 like 'teststring_%' ORDER BY text1;
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| select * from t1 where text1='teststring' or text1 like 'teststring_%';
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| select * from t1 where text1='teststring' or text1 > 'teststring\t';
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| select * from t1 order by text1;
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| explain select * from t1 order by text1;
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| 
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| alter table t1 modify text1 char(32) binary not null;
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| check table t1;
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| select * from t1 ignore key (key1) where text1='teststring' or 
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|   text1 like 'teststring_%' ORDER BY text1;
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| select concat('|', text1, '|') from t1 where text1='teststring' or text1 like 'teststring_%';
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| select concat('|', text1, '|') from t1 where text1='teststring' or text1 > 'teststring\t';
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| select text1, length(text1) from t1 order by text1;
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| select text1, length(text1) from t1 order by binary text1;
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| 
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| alter table t1 modify text1 blob not null, drop key key1, add key key1 (text1(20));
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| insert into t1 values ('teststring ');
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| select concat('|', text1, '|') from t1 order by text1;
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| select concat('|', text1, '|') from t1 where text1='teststring' or text1 > 'teststring\t';
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| select concat('|', text1, '|') from t1 where text1='teststring';
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| select concat('|', text1, '|') from t1 where text1='teststring ';
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| 
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| alter table t1 modify text1 text not null, pack_keys=1;
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| select concat('|', text1, '|') from t1 where text1='teststring';
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| select concat('|', text1, '|') from t1 where text1='teststring ';
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| explain select concat('|', text1, '|') from t1 where text1='teststring ';
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| select concat('|', text1, '|') from t1 where text1 like 'teststring_%';
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| select concat('|', text1, '|') from t1 where text1='teststring' or text1 like 'teststring_%';
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| select concat('|', text1, '|') from t1 where text1='teststring' or text1 > 'teststring\t';
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| select concat('|', text1, '|') from t1 order by text1;
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| drop table t1;
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| 
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| create table t1 (text1 varchar(32) not NULL, KEY key1 (text1)) pack_keys=0;
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| insert into t1 values ('teststring'), ('nothing'), ('teststring\t');
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| select concat('|', text1, '|') from t1 where text1='teststring' or text1 like 'teststring_%';
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| select concat('|', text1, '|') from t1 where text1='teststring' or text1 >= 'teststring\t';
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| drop table t1;
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| 
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| # Test HEAP tables (with BTREE keys)
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| 
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| create table t1 (text1 varchar(32) not NULL, KEY key1 using BTREE (text1)) engine=heap;
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| insert into t1 values ('teststring'), ('nothing'), ('teststring\t');
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| select * from t1 ignore key (key1) where text1='teststring' or 
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|   text1 like 'teststring_%' ORDER BY text1;
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| select * from t1 where text1='teststring' or text1 like 'teststring_%';
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| select * from t1 where text1='teststring' or text1 >= 'teststring\t';
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| select * from t1 order by text1;
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| explain select * from t1 order by text1;
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| 
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| alter table t1 modify text1 char(32) binary not null;
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| select * from t1 order by text1;
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| drop table t1;
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| 
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| #
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| # Test InnoDB tables
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| #
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| 
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| create table t1 (text1 varchar(32) not NULL, KEY key1 (text1)) engine=innodb;
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| insert into t1 values ('teststring'), ('nothing'), ('teststring\t');
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| check table t1;
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| select * from t1 where text1='teststring' or text1 like 'teststring_%';
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| select * from t1 where text1='teststring' or text1 > 'teststring\t';
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| select * from t1 order by text1;
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| explain select * from t1 order by text1;
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| 
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| alter table t1 modify text1 char(32) binary not null;
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| select * from t1 order by text1;
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| 
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| alter table t1 modify text1 blob not null, drop key key1, add key key1 (text1(20));
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| insert into t1 values ('teststring ');
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| select concat('|', text1, '|') from t1 order by text1;
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| 
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| alter table t1 modify text1 text not null, pack_keys=1;
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| select * from t1 where text1 like 'teststring_%';
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| 
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| # The following gives wrong result in InnoDB
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| select text1, length(text1) from t1 where text1='teststring' or text1 like 'teststring_%';
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| select text1, length(text1) from t1 where text1='teststring' or text1 >= 'teststring\t';
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| select concat('|', text1, '|') from t1 order by text1;
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| drop table t1;
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| 
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| # End of 4.1 tests
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