RE: Execution plan for queries using minus/union/intersect
From: Allen, Brandon <Brandon.Allen_at_OneNeck.com>
Date: Thu, 22 Oct 2009 13:59:23 -0700
Message-ID: <64BAF54438380142A0BF94A23224A31E112CC3F03E_at_ONEWS06.oneneck.corp>
Not sure if I understand correctly what you're trying to do, but maybe a UNION ALL is what you're looking on the UNION option, but not sure about the MINUS and INTERSECT, however I'd imagine that if there is a unique index on the relevant columns of both tables then Oracle will be smart enough to avoid actually doing any sorting even though it might still show the SORT step in the plan, there wouldn't be any real work behind it. Just guessing here so everyone feel free to jump in and correct me.
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Date: Thu, 22 Oct 2009 13:59:23 -0700
Message-ID: <64BAF54438380142A0BF94A23224A31E112CC3F03E_at_ONEWS06.oneneck.corp>
Not sure if I understand correctly what you're trying to do, but maybe a UNION ALL is what you're looking on the UNION option, but not sure about the MINUS and INTERSECT, however I'd imagine that if there is a unique index on the relevant columns of both tables then Oracle will be smart enough to avoid actually doing any sorting even though it might still show the SORT step in the plan, there wouldn't be any real work behind it. Just guessing here so everyone feel free to jump in and correct me.
Regards,
Brandon
Privileged/Confidential Information may be contained in this message or attachments hereto. Please advise immediately if you or your employer do not consent to Internet email for messages of this kind. Opinions, conclusions and other information in this message that do not relate to the official business of this company shall be understood as neither given nor endorsed by it.
-- http://www.freelists.org/webpage/oracle-lReceived on Thu Oct 22 2009 - 15:59:23 CDT