Re: BUG #2126: Index usage for function value - Mailing list pgsql-bugs

From Tom Lane
Subject Re: BUG #2126: Index usage for function value
Date
Msg-id 23098.1135697052@sss.pgh.pa.us
Whole thread Raw
In response to BUG #2126: Index usage for function value  ("Grzegorz Tańczyk" <goliatus@polzone.pl>)
List pgsql-bugs
"Grzegorz TaÅczyk" <goliatus@polzone.pl> writes:
> SELECT * FROM table WHERE id = myfunction('x', 10);
> There is an index created on id column, but query planner doesn't use it.

Have you declared myfunction as IMMUTABLE or STABLE?  If it's volatile
then optimizing to an indexscan is incorrect and the planner won't do it.

            regards, tom lane

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