Re: Multiple queries into a single temp table

Alexander V.Didytch wrote: > Jay Hannah wrote: > > Here are a couple solutions for you: > > > > 1) Use the UNION operator: > > select id as col1, dealer as col2 from dealer > > UNION -- (or UNION ALL) > > select id as col1, manufacturer as col2 from manufacturer > > into temp dlr_manu_tbl;> > > > 2) Create the temporary table as a seperate step: > > create TEMP table dlr_manu_tbl (col1 int, col2 varchar(40)); > > insert into dlr_manu_tbl > > select id as col1, dealer as col2 from dealer; > > insert into dlr_manu_tbl > > select id as col1, manufacturer as col2 from manufacturer;> > > > Could someone tell me about performance of each approach ?. > Which solution is more preferable with terrific amount of data in each select My completely uneducated guess would be that with very large amounts of data, the second method may be faster since it ties up less memory per transaction... If I were you, I'd just run them both and see which one completes faster (but I'm goofy like that). Jay