"Markus Wollny" <Markus(dot)Wollny(at)computec(dot)de> writes:
> I would like to know why this query here doesn't use the index on
> ct_com_board_message....
> from CT_COM_BOARD_MESSAGE MESSAGE
> where (0=0)
> and (MESSAGE.CREATED >= CURRENT_TIMESTAMP-1)
> LIMIT 500
That's not considered an indexable WHERE clause in current releases
(7.3 will fix this). See past discussions about how to hide the
current_timestamp call in a function marked "isCachable".
regards, tom lane