diff options
Diffstat (limited to 'doc/src/sgml/ref/select.sgml')
| -rw-r--r-- | doc/src/sgml/ref/select.sgml | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml index ab91105599..9c5cf50ef0 100644 --- a/doc/src/sgml/ref/select.sgml +++ b/doc/src/sgml/ref/select.sgml @@ -37,7 +37,7 @@ SELECT [ ALL | DISTINCT [ ON ( <replaceable class="parameter">expression</replac [ * | <replaceable class="parameter">expression</replaceable> [ [ AS ] <replaceable class="parameter">output_name</replaceable> ] [, ...] ] [ FROM <replaceable class="parameter">from_item</replaceable> [, ...] ] [ WHERE <replaceable class="parameter">condition</replaceable> ] - [ GROUP BY <replaceable class="parameter">grouping_element</replaceable> [, ...] ] + [ GROUP BY [ ALL | DISTINCT ] <replaceable class="parameter">grouping_element</replaceable> [, ...] ] [ HAVING <replaceable class="parameter">condition</replaceable> ] [ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceable class="parameter">window_definition</replaceable> ) [, ...] ] [ { UNION | INTERSECT | EXCEPT } [ ALL | DISTINCT ] <replaceable class="parameter">select</replaceable> ] @@ -778,7 +778,7 @@ WHERE <replaceable class="parameter">condition</replaceable> <para> The optional <literal>GROUP BY</literal> clause has the general form <synopsis> -GROUP BY <replaceable class="parameter">grouping_element</replaceable> [, ...] +GROUP BY [ ALL | DISTINCT ] <replaceable class="parameter">grouping_element</replaceable> [, ...] </synopsis> </para> @@ -802,7 +802,10 @@ GROUP BY <replaceable class="parameter">grouping_element</replaceable> [, ...] independent <replaceable>grouping sets</replaceable>. The effect of this is equivalent to constructing a <literal>UNION ALL</literal> between subqueries with the individual grouping sets as their - <literal>GROUP BY</literal> clauses. For further details on the handling + <literal>GROUP BY</literal> clauses. The optional <literal>DISTINCT</literal> + clause removes duplicate sets before processing; it does <emphasis>not</emphasis> + transform the <literal>UNION ALL</literal> into a <literal>UNION DISTINCT</literal>. + For further details on the handling of grouping sets see <xref linkend="queries-grouping-sets"/>. </para> |