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Optimizing MySQL query

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I have a MySQL Query which has Join statement, left side of the join statement returns 1800 rows and right side is about 1500 after join I jut need top 50 rows. Total operation takes about 5 sec.
Any suggestions?

posted Oct 15, 2013 by Salil Agrawal

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1 Answer

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Try joining in two steps, say 1800 X 750 select 50 followed by 1800 X 750 select 50 union all select 50. This should reduce the operation time significantly.

answer Oct 16, 2013 by Deepankar Dubey
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Joiner using how to get three tables value fetching from single query.

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I'm noticing that across our several databases and hundreds of tables that column definitions are not consistent. I'm wondering if there is a tool or query (using INFORMATION_SCHEMA perhaps) that will show me all databases, tables and columns where they don't match (by column name).

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