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Update discussion of aggregate syntax to mention ALL.

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Tom Lane 2000-02-21 01:20:41 +00:00
parent a7f85783fb
commit f72aad5678
1 changed files with 3 additions and 1 deletions
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doc/src/sgml/syntax.sgml
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@ -711,6 +711,7 @@ sqrt(emp.salary)
<simplelist>
<member><replaceable>aggregate_name</replaceable> (<replaceable>expression</replaceable>)</member>
<member><replaceable>aggregate_name</replaceable> (ALL <replaceable>expression</replaceable>)</member>
<member><replaceable>aggregate_name</replaceable> (DISTINCT <replaceable>expression</replaceable>)</member>
<member><replaceable>aggregate_name</replaceable> ( * )</member>
</simplelist>
@ -723,7 +724,8 @@ sqrt(emp.salary)
<para>
The first form of aggregate expression invokes the aggregate across all
input rows for which the given expression yields a non-null value.
The second form invokes the aggregate for all distinct non-null values
The second form is the same as the first, since ALL is the default.
The third form invokes the aggregate for all distinct non-null values
of the expression found in the input rows. The last form invokes the
aggregate once for each input row regardless of null or non-null values;
since no particular input value is specified, it is generally only useful