Bug #2925 LIKE "string%" does not work correctly on VARHCAR with partial index in MERGE t
Submitted: 23 Feb 2004 9:08 Modified: 23 Feb 2004 10:27
Reporter: SINISA MILIVOJEVIC Email Updates:
Status: Not a Bug Impact on me:
None 
Category:MySQL Server Severity:S2 (Serious)
Version:4.0.18 OS:Any (any)
Assigned to: Sergei Golubchik CPU Architecture:Any

[23 Feb 2004 9:08] SINISA MILIVOJEVIC
Description:
Queries which contain LIKE "string%" in the WHERE clause do not work correctly on VARHCAR with partial index in MERGE tables.

How to repeat:

mysql> create table t1 (c varchar(192), key cc (c(10)));
Query OK, 0 rows affected (0.01 sec)

mysql> create table t2 (c varchar(192), key cc (c(10)));
Query OK, 0 rows affected (0.01 sec)

mysql> insert into t2 values ("sinisa@mysql.com");
Query OK, 1 row affected (0.02 sec)

mysql> insert into t1 values ("sinisa@mysqlcom");
Query OK, 1 row affected (0.00 sec)

mysql> create table t (c char(192), key cc (c(10))) type=mrg_myisam union=(t1,t2);
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> select * from t where c like "sinisa%";
Empty set (0.00 sec)

mysql> select * from t1 where c like "sinisa%";
+----------------------+
| c                    |
+----------------------+
| sinisa@mysql.com     |
+----------------------+
1 row in set (0.00 sec)

mysql> select * from t2 where c like "sinisa%";
+----------------------+
| c                    |
+----------------------+
| sinisa@mysql.com     |
+----------------------+
1 row in set (0.00 sec)

mysql> select * from t where c like "sinisa%";
Empty set (0.00 sec)
[23 Feb 2004 10:27] Sergei Golubchik
Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.mysql.com/documentation/ and the instructions on
how to report a bug at http://bugs.mysql.com/how-to-report.php

Additional info:

MERGE table should have the same structure as underlying MyISAM tables.
You have declared a column as CHAR in MERGE table and VARCHAR in MyISAM tables.