Bug #20680 It is not possible to determine which key cache a particular table uses
Submitted: 24 Jun 2006 20:48 Modified: 25 Jun 2006 14:49
Reporter: J Rabbit Email Updates:
Status: Verified Impact on me:
None 
Category:MySQL Server: MyISAM storage engine Severity:S4 (Feature request)
Version:5.0.22 OS:Microsoft Windows (Windows 2003)
Assigned to: CPU Architecture:Any
Triage: Triaged: D5 (Feature request)

[24 Jun 2006 20:48] J Rabbit
Description:
If you assign a table to a custom key cache using the CACHE INDEX statement it is not possible to determine at a later date that this has happened.

How to repeat:
SET GLOBAL test.key_buffer_size=1000000;
CREATE TABLE t1 (c1 int primary key);
CACHE INDEX t1 IN test;
SHOW INDEX FORM t1;

The output does not indicate that the index is cached in the test cache.

Suggested fix:
Add a column to the output of the SHOW INDEX statement to indicate which key cache each index uses. Although all indexes on a table use the same cache at present, adding the column to SHOW INDEX rather than SHOW TABLE STATUS would cater for any future enhancment to allow individual indexes to be assigned to caches.
[25 Jun 2006 14:49] Valeriy Kravchuk
Thank you for a reasonable feature request.