Bug #45492 changing delay_key_write option should not copy rows
Submitted: 15 Jun 2009 6:10
Reporter: Mikiya Okuno Email Updates:
Status: Verified Impact on me:
Category:MySQL Server: MyISAM storage engine Severity:S4 (Feature request)
Version: OS:Any
Assigned to: CPU Architecture:Any

[15 Jun 2009 6:10] Mikiya Okuno
Currently, changing delay_key_write option using ALTER TABLE command copies all table rows to a temporary table during alteration. However, it is totally unnecessary. Changing this attribute should not copy rows like when changing the table name using RENAME TABLE command.

If we can use delayed key write on demand, loading huge amount of rows to MyISAM table will be much faster than now. Otherwise, we should do ALTER TABLE which will copy all rows internally.

How to repeat:

Suggested fix:
[3 Mar 2010 9:31] Sveta Smirnova
Bug #51680 was marked as duplicate of this one.