Does the order of columns in a query matter?

Posted by James Simpson on Stack Overflow See other posts from Stack Overflow or by James Simpson
Published on 2011-01-03T05:52:36Z Indexed on 2011/01/03 5:53 UTC
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mysql

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mysql-query

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query-optimization

When selecting columns from a MySQL table, is performance affected by the order that you select the columns as compared to their order in the table (not considering indexes that may cover the columns)?

For example, you have a table with rows uid, name, bday, and you have the following query.

SELECT uid, name, bday FROM table

Does MySQL see the following query any differently and thus cause any sort of performance hit?

SELECT uid, bday, name FROM table

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