Bug #47785 DDL fails due to BLOB/TEXT used in key specification without a key length

• Submitted: 2 Oct 2009 9:49
• Modified: 5 Nov 2012 12:12
• Reporter: Shane Bester (Platinum Quality Contributor)
• Status: Can't repeat
• Category: MySQL Server: DDL
• Severity: S3 (Non-critical)
• Version: >=5.0.30, 5.0.85, 5.1.39,5.5.99-m3
• OS: Any
• CPU Architecture: Any
• Tags: regression

[2 Oct 2009 9:49] Shane Bester

Description:
a table that is created successfully with prefix index of certain charsets, cannot be altered to change the engine, or rebuild the table with same engine:

mysql> create table `t1` (`c4` tinytext character set euckr,key (`c4`(128))) engine=myisam;
Query OK, 0 rows affected (0.00 sec)

mysql> alter table t1 engine=myisam;
ERROR 1170 (42000): BLOB/TEXT column 'c4' used in key specification without a key length

How to repeat:
drop table if exists t1;
create table `t1` (`c4` tinytext character set euckr,key (`c4`(128))) engine=myisam;
alter table t1 engine=myisam;

Suggested fix:
just make it work

[2 Oct 2009 10:02] Sveta Smirnova

Thank you for the report.

Verified as described.

[5 Nov 2012 12:12] Jon Olav Hauglid

Not repeatable with 5.5.29