Bug #32916 Character sets: comparisons with supersets fail
Submitted: 2 Dec 2007 22:29 Modified: 2 Dec 2007 22:34
Reporter: Peter Gulutzan Email Updates:
Status: Verified Impact on me:
None 
Category:MySQL Server: Charsets Severity:S3 (Non-critical)
Version:6.0.4-alpha-debug OS:Linux (SUSE 10 64-bit)
Assigned to: Assigned Account CPU Architecture:Any

[2 Dec 2007 22:29] Peter Gulutzan 
Description:
If character set X is a proper subset of character set Y,
then comparisons _x '...' = _y '...' should work.
They don't work with the new character sets in MySQL 6.0.

How to repeat:
mysql> select _ucs2 'a' = _utf32 'a';
ERROR 1267 (HY000): Illegal mix of collations (ucs2_general_ci,COERCIBLE) and (utf32_general_ci,COERCIBLE) for operation '='
mysql> select _utf8mb3 'a' = _utf8 'a';
ERROR 1267 (HY000): Illegal mix of collations (utf8mb3_general_ci,COERCIBLE) and (utf8_general_ci,COERCIBLE) for operation '='
[2 Dec 2007 22:34] MySQL Verification Team 
Thank you for the bug report. Verified as described.