I have two very similar queries which I need to execute. They both have
exactly the same from / where conditions. When I execute the first, it takes
about 16 seconds. The second is executed almost immediately after, it takes
13 seconds. In short, I'd like to know why the query result isn't being
cached and any ideas on how to improve the execution.


<snip>


OK - so I could execute the query once, and get the maximum size of the
array and the result set in one. I know what I am doing is less than optimal
but I had expected the query results to be cached. So the second execution
would be very quick. So why aren't they ? I have increased my cache size -
shared_buffers is 2000 and I have doubled the default max_fsm... settings
(although I am not sure what they do). sort_mem is 8192.

PostgreSQL does not have, and has never had a query cache - so nothing you do is going to make that second query faster.


Perhaps you are confusing it with the MySQL query cache?

Chris


---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend

Reply via email to