Re: Long query execution times for union

Thomas J. Kyte wrote:
>
> Select * from T
> union

etc., etc...  

> Thomas Kyte
> Oracle Government
> tkyte_at_us.oracle.com
>
> http://govt.us.oracle.com -- Check out our web site! Brand new, uses Oracle Web Server and Database
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> -------------------
>
> statements and opinions are mine and do not necessarily
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The union all did it. I got several responses along this line, but most mentioned that Oracle would compare the rows returned by each select to exclude the duplicates. Each select I was doing was returning only 10-20 rows, but that was with an extra condition. Adding the 'UNION ALL' made the difference.

Thanks for all the responses!

Eric Ladner          | UNIX/Oracle/Passport Sys-Administration, General
clad_at_chevron.com     | Applications Development, etc., etc. 
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