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MySQL Cross Schema Joins

Posted on 2007-03-20
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Doing a lot of cross schema joins for some shared data...

SELECT cols FROM schema1.table INNER JOIN schema2.table ...


Just curious if there is any particular caveats to doing this?  Any special indexes that need to be created, any optimization tips...
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Question by:mynamebecory2
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dodge20 earned 100 total points
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Generally the rule of thumb is that any field that you use as a join should have an index. There may be some exceptions, but you are pretty safe doing this. Otherwise no caveats. Pretty standard in databases.
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