Bug #16619 information_schema database corrupted following disk space error
Submitted: 18 Jan 2006 22:03 Modified: 18 Jan 2006 22:52
Reporter: Michael Chester Email Updates:
Status: Not a Bug Impact on me:
None 
Category:MySQL Server Severity:S2 (Serious)
Version:5.0.13-rc-standard OS:Linux (RHEL4)
Assigned to: CPU Architecture:Any

[18 Jan 2006 22:03] Michael Chester 
Description:
Following a disk out of space error for '/tmp' the 'information_schema' database is reporting an error 28 for the COLUMNS, ROUTINES, TRIGGERS, and VIEWS tables - even though none of the OS file systems is more than 45% full.  This affects applications that use these tables, triggers, views, etc, but strangely not local connections using the mysql command line tool as long as you don't try to do anything fancy.

How to repeat:
1. Flood the '/tmp' filesystem so that it is completely full.
2. Attempt several substantial sql operations (LOAD DATA INFILE seems to do the trick).  
3. Clear the offending files from the '/tmp' filesystem.
4. Check the entries in the 'information_schema' database table 'TABLES' for the comment 'Got error 28 from storage engine.'

To see the effect of the error try browsing the catalogs using the administration tool.  I used version 1.1.6 and got a nice little pop-up box giving me the comment from the 'TABLES' comment column.
[18 Jan 2006 22:04] Michael Chester 
Can the information_schema database be repaired or recreated?
[18 Jan 2006 22:52] Michael Chester 
This error was caused by another application generating random temporary files.  It is not a bug, my apologies.