Bug #51180 explain_filename cannot explain #sql temporary file names

• Submitted: 15 Feb 2010 7:49
• Modified: 28 May 2013 9:27
• Reporter: Marko Mäkelä
• Status: Closed
• Category: MySQL Server
• Severity: S3 (Non-critical)
• Version: 5.1.41+
• OS: Any
• Assigned to: Mattias Jonsson
• CPU Architecture: Any

[15 Feb 2010 7:49] Marko Mäkelä

Description:
The function explain_filename, which was supposed to fix Bug #32430, fails to account for temporary table names that start with #sql.

An excerpt from a Bug #35077 comment demonstrates the bug:

100210 16:57:57  InnoDB: Error: table 100210 16:57:57 [Warning] Invalid (old?) table or
database name '#sql2-4947-72390'
`mydb`.<result 2 when explaining filename '#sql2-4947-72390'> does not exist in the
InnoDB internal
InnoDB: data dictionary though MySQL is trying to drop it.

How to repeat:
Kill mysqld at a suitable moment in mysql_alter_table (sql/sql_table.cc) and restart it. Or, alternatively, copy the .frm file and try DROP TABLE '#mysql50##sql…';

Suggested fix:
Make explain_filename replace the table name prefix #sql with #mysql50##sql and copy the rest of the string as UTF-8 (system_charset_info).

[28 May 2013 9:27] Mattias Jonsson

explain_filename is now only explaining partition names, and does simply return the rest as is.