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Adjust documentation wording of window function ORDER BY to not mention

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avg() because it was inaccurate.
This commit is contained in:
Bruce Momjian 2011-02-20 00:01:08 -05:00
parent 8c0f1e2762
commit d5813488a4
1 changed files with 4 additions and 4 deletions
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doc/src/sgml/advanced.sgml
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@ -383,10 +383,10 @@ SELECT depname, empno, salary, avg(salary) OVER (PARTITION BY depname) FROM emps
</para>
<para>
Although <function>avg</> will produce the same result no matter
what order it processes the partition's rows in, this is not true of all
window functions. When needed, you can control that order using
<literal>ORDER BY</> within <literal>OVER</>. Here is an example:
You can also control the order in which rows are processed by
window functions using <literal>ORDER BY</> within <literal>OVER</>.
(The window <literal>ORDER BY</> does not even have to match the
order in which the rows are output.) Here is an example:
<programlisting>
SELECT depname, empno, salary, rank() OVER (PARTITION BY depname ORDER BY salary DESC) FROM empsalary;