MySQL GROUP BY and ORDER BY order

Question

Does it matter which comes after which? I mean if I do

SELECT * FROM  table GROUP BY x ORDER BY y

will the results first be grouped and then ordered?

It is a syntax error to put the `ORDER BY` first. It is always evaluated last, and must occur after the `GROUP BY`. — Michael Berkowski, Oct 31 '12 at 13:16

John Woo · Accepted Answer · 2012-10-31T13:25:08.523

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ORDER is the last clause to be executed.

The order of execution

FROM clause
WHERE clause (the reason why you can't use alias on this clause)
GROUP BY clause
HAVING clause
SELECT clause
ORDER BY clause

^{For more info, please click here}

edited Oct 31 '12 at 13:25

answered Oct 31 '12 at 13:15

John Woo

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@xyu added some source link :D – John Woo Oct 31 '12 at 13:19
Also here, [an SO question](http://stackoverflow.com/questions/6545664/using-case-expression-column-in-where-clause/6545685#6545685) – ypercubeᵀᴹ Nov 01 '12 at 22:26

score 1 · Answer 2 · edited Oct 31 '12 at 13:39

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First WHERE condition
Second GROUP BY
Third one is ORDER BY

Example :

SELECT * FROM table GROUP BY columnanme ORDER BY columnanmae

edited Oct 31 '12 at 13:39

Tom Seidel

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answered Oct 31 '12 at 13:16

Vikram Jain

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score 0 · Answer 3 · answered Oct 31 '12 at 13:21

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In MySQL, a GROUP BY clause has the side effect of sorting columns as well. If you already have a GROUP BY clause in your query that produces the desired sort order, there's no need for an ORDER BY.

answered Oct 31 '12 at 13:21

GregD

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MySQL GROUP BY and ORDER BY order

3 Answers3