Hi,
I have a question on implementation of the LIMIT SQL clause.
Using the LIMIT clause, I want to reduce the computation time for a query.
When I try to limit the result of a joined table, however, the join will be computed first (which takes very long).
Lets suppose the following example:
select * from T1 join T2 on T1.id = T2.id LIMIT 1
Conceptually, it should be possible to fetch one row from T1 and T2, i.e. to propagate the LIMIT clause.
I was wondering what the exact requirements are to propagate the LIMIT clause.
Do I need a foreign key relation between T1 and T2?
Do I need to use a full outer join in order to propagate the LIMIT clause?
Thanks
Gregor Zeitlinger
LUCAS Product Development
Torex Retail Solutions GmbH
Schwedenstr. 9, D-13359 Berlin
Tel. +49 (0) 30 49901-243
Fax +49 (0) 30 49901-139
Mailto:gregor.zeitlinger@torexretail.de
http://www.torexretail.de
