diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml index a33a537bd484d5bc0e5c076fae1c31e16d4f5e51..ff5d68126042b65e39128c93426a677c0b6eb1ab 100644 --- a/doc/src/sgml/ref/select.sgml +++ b/doc/src/sgml/ref/select.sgml @@ -1,5 +1,5 @@ <!-- -$PostgreSQL: pgsql/doc/src/sgml/ref/select.sgml,v 1.119 2009/01/23 14:05:28 momjian Exp $ +$PostgreSQL: pgsql/doc/src/sgml/ref/select.sgml,v 1.120 2009/02/02 20:42:57 tgl Exp $ PostgreSQL documentation --> @@ -1002,6 +1002,13 @@ OFFSET <replaceable class="parameter">start</replaceable> class="parameter">count</replaceable> rows to be returned. </para> + <para> + If the <replaceable class="parameter">count</replaceable> expression + evaluates to NULL, it is treated as <literal>LIMIT ALL</>, i.e., no + limit. If <replaceable class="parameter">start</replaceable> evaluates + to NULL, it is treated the same as <literal>OFFSET 0</>. + </para> + <para> SQL:2008 introduced a different syntax to achieve the same thing, which PostgreSQL also supports. It is: @@ -1014,10 +1021,11 @@ FETCH { FIRST | NEXT } [ <replaceable class="parameter">count</replaceable> ] { the <literal>FETCH</literal> clause. <literal>ROW</literal> and <literal>ROWS</literal> as well as <literal>FIRST</literal> and <literal>NEXT</literal> are noise words that don't influence - the effects of these clauses. When using expressions other than - constants for the offset or fetch count, parentheses will be - necessary in most cases. If the fetch count is omitted, it - defaults to 1. + the effects of these clauses. In this syntax, when using expressions + other than simple constants for <replaceable class="parameter">start</> + or <replaceable class="parameter">count</replaceable>, parentheses will be + necessary in most cases. If <replaceable class="parameter">count</> is + omitted in <literal>FETCH</>, it defaults to 1. </para> <para>