Home Forums SQL Server 2008 T-SQL (SS2K8) Some way to write an INNER JOIN, but joining on either of two columns RE: Some way to write an INNER JOIN, but joining on either of two columns

  • matt6749 (10/29/2012)


    Hi,

    Each doctor in my doctors table has a main zip code and an alternate zip code.

    SELECT D.*

    FROM Doctors D

    INNER JOIN ZipCodes Z

    ON D.MainZip = Z.ZipCode

    OR D.AlternateZip = Z.ZipCode

    I've been trying, but can't figure out how to do this (the OR part).. thanks.

    Your query can probably be made to work. Try this:

    DECLARE @doctors TABLE (name VARCHAR(10), MainZip VARCHAR(5), AlternateZip VARCHAR(5))

    INSERT INTO @doctors

    SELECT 'Dr. Dwain', '12345', NULL

    UNION ALL SELECT 'Dr. Jeff', NULL, '12346'

    UNION ALL SELECT 'Dr. Chris', '12345', '12347'

    UNION ALL SELECT 'Dr. Paul', '22222', '33333'

    DECLARE @ZipCodes TABLE (ZipCode VARCHAR(5))

    INSERT INTO @ZipCodes

    SELECT '12345' UNION ALL SELECT '12346' UNION ALL SELECT '12347'

    -- Returns 2 results of Dr. Chris

    SELECT D.*

    FROM @doctors D

    INNER JOIN @ZipCodes Z

    ON D.MainZip = Z.ZipCode

    OR D.AlternateZip = Z.ZipCode

    If the issue is dups being returned, add DISTINCT to your SELECT.

    Otherwise, look at CELKO's method. That should work too.


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