--On 24. Januar 2010 19:45:33 +0100 Bernd Helmle <maili...@oopsware.de>
wrote:
I don't see where this should be related to the number of tables not
part of the inheritance tree (or inheritance at all).
To answer that myself: it seems get_attname() introduces the overhead here
(forgot about that). Creating additional 16384 tables without any
connection to the inheritance increases the times on my Phenom-II Box to
round about 2 seconds:
Current -HEAD
bernd=# ALTER TABLE a1 RENAME COLUMN acol1 TO xyz;
ALTER TABLE
Time: 409,045 ms
With KaiGai's recent patch:
bernd=# ALTER TABLE a1 RENAME COLUMN acol1 TO xyz;
ALTER TABLE
Time: 2402,306 ms
--
Thanks
Bernd
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