Bug #22367: Optimizer uses ref join type instead of eq_ref for simple join on

             strings
MySQL is setting the flag HA_END_SPACE_KEYS for all the keys that reference
text or varchar columns with collation different than binary.
This was done to handle correctly the situation where a lookup on such a key
may return more than 1 row because of the presence of many rows that differ
only by the amount of trailing space in the table's string column.
Inserting such values however appears to violate the unique checks on 
INSERT/UPDATE. Thus that flag must not be set as it will prevent the optimizer
from choosing a faster access method.
This fix removes the setting of the HA_END_SPACE_KEYS flag.


include/my_base.h:
  Bug #22367: Optimizer uses ref join type instead of eq_ref for simple join on 
               strings
   - disabled HA_END_SPACE_KEY as it's no longer needed
mysql-test/r/func_str.result:
  Bug #22367: Optimizer uses ref join type instead of eq_ref for simple join on 
               strings
   - fixed explain in an existing case
mysql-test/r/merge.result:
  Bug #22367: Optimizer uses ref join type instead of eq_ref for simple join on 
               strings
   - fixed explain in an existing case
mysql-test/r/select.result:
  Bug #22367: Optimizer uses ref join type instead of eq_ref for simple join on 
               strings
   - test case
mysql-test/r/subselect.result:
  Bug #22367: Optimizer uses ref join type instead of eq_ref for simple join on 
               strings
   - fixed explain in an existing case
mysql-test/t/select.test:
  Bug #22367: Optimizer uses ref join type instead of eq_ref for simple join on 
               strings
   - test case

1 files changed, 2 insertions, 2 deletions

diff --git a/mysql-test/r/func_str.result b/mysql-test/r/func_str.result
index 00642e1a570..c2c12f8d291 100644
--- a/mysql-test/r/func_str.result
+++ b/mysql-test/r/func_str.result
@@ -1143,9 +1143,9 @@ EXPLAIN EXTENDED
 SELECT * FROM t1 INNER JOIN t2 ON code=id 
 WHERE id='a12' AND (LENGTH(code)=5 OR code < 'a00');
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	const	PRIMARY	PRIMARY	12	const	1	Using index
 1	SIMPLE	t1	ref	code	code	13	const	3	Using where; Using index
-1	SIMPLE	t2	ref	PRIMARY	PRIMARY	12	const	1	Using where; Using index
 Warnings:
-Note	1003	select `test`.`t1`.`code` AS `code`,`test`.`t2`.`id` AS `id` from `test`.`t1` join `test`.`t2` where ((`test`.`t1`.`code` = _latin1'a12') and (`test`.`t2`.`id` = _latin1'a12') and (length(`test`.`t1`.`code`) = 5))
+Note	1003	select `test`.`t1`.`code` AS `code`,`test`.`t2`.`id` AS `id` from `test`.`t1` join `test`.`t2` where ((`test`.`t1`.`code` = _latin1'a12') and (length(`test`.`t1`.`code`) = 5))
 DROP TABLE t1,t2;
 End of 5.0 tests