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is there a significant speed difference between INNER JOIN and LEFT OUTER JOIN? - ASP Database

Hello, If I do this: SELECT bla FROM a, b, c WHERE a.fff = AND b.sfdd = AND c.asa = is it any faster than doing something like this?: SELECT bla FROM a LEFT JOIN a stuff LEFT JOIN b stuff LEFT JOIN c stuff Thanks, Mike...

  1. #1

    Default is there a significant speed difference between INNER JOIN and LEFT OUTER JOIN?

    Hello,

    If I do this:

    SELECT bla FROM a, b, c
    WHERE
    a.fff =
    AND
    b.sfdd =
    AND
    c.asa =

    is it any faster than doing something like this?:

    SELECT bla FROM a
    LEFT JOIN
    a stuff
    LEFT JOIN
    b stuff
    LEFT JOIN
    c stuff

    Thanks,
    Mike
    Mike Guest

  2. #2

    Default Re: is there a significant speed difference between INNER JOIN and LEFT OUTER JOIN?

    These are not the same queries. The first query is an INNER JOIN, which
    will only return rows that match in all three tables. Did you even run the
    queries to see the difference?

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    "Mike" <com> wrote in message
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    Aaron Guest

  3. #3

    Default Re: is there a significant speed difference between INNER JOIN and LEFT OUTER JOIN?

    To answer the question raised in your subject: yes. Outer joins cannot be
    optimized as inner joins can be.

    Mike wrote: 

    To answer this question: yes, the first query will be faster, but it may not
    give you the results you require.

    Bob Barrows

    --
    Microsoft MVP - ASP/ASP.NET
    Please reply to the newsgroup. This email account is my spam trap so I
    don't check it very often. If you must reply off-line, then remove the
    "NO SPAM"


    Bob Guest

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