db-derby-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Bryan Pendleton <bpendle...@amberpoint.com>
Subject Re: slow subqueries
Date Sat, 11 Nov 2006 19:46:02 GMT
> This is why a nested loop is not going to work here... 20,000 squared
> operations is very expensive, let alone millions squared.  For a query with
> this profile, the inner query should only be executed once. 

Perhaps you can get the behavior you desire by explicitly creating
a temporary table, selecting the data from your inner query into
the temporary table, then re-writing your main query to join against
the temporary table?



View raw message