SQL Server Performance

Left outer joins are faster than inner joins

Discussion in 'SQL Server 2005 T-SQL Performance Tuning' started by Anirban Biswas, Feb 14, 2008.

  1. Anirban Biswas New Member

    Hi,
    I am using derieved tables and using left outer join with other tables.
    Can any one tell me if Left outer joins are faster than inner joins
  2. Madhivanan Moderator

    Not neccessary
    Set the execution plan and see
    Dont use left join when inner join is needed
  3. FrankKalis Moderator

    What makes you think so?
  4. FrankKalis Moderator

    [quote user="FrankKalis"]
    What makes you think so?
    [/quote]
    Oops, my reply is aimed at the OP.
  5. ScottPletcher New Member

    Inner joins should be faster than left outer joins, esp. multiple IJs vs. multiple LOJs.
  6. Adriaan New Member

    And let's not forget that OP is talking about a join involving a derived table.
    Indeed inner joins are usually faster than left joins, but if you need a left join (for "unmatched results") then an inner join will not give you the results that you need.
    If you are filtering on the "right" table in a left join, then indeed you should use an inner join instead, and you may get better performance.
  7. satya Moderator

    Don't you all think this sounds like a classroom based exercise or homework [:)]?

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