Clarify documentation about SQL:2008 variant of LIMIT/OFFSET syntax.

tglsfdc · tglsfdc · commit da1eacb8d2ce · 2011-12-01T16:39:07.000-05:00
The point that you need parentheses for non-constant expressions apparently
needs to be brought out a bit more clearly, per bug #6315.
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
@@ -1056,17 +1056,19 @@ OFFSET <replaceable class="parameter">start</replaceable>
 OFFSET <replaceable class="parameter">start</replaceable> { ROW | ROWS }
 FETCH { FIRST | NEXT } [ <replaceable class="parameter">count</replaceable> ] { ROW | ROWS } ONLY
 </synopsis>
-    According to the standard, the <literal>OFFSET</literal> clause must come
-    before the <literal>FETCH</literal> clause if both are present; but
-    <productname>PostgreSQL</> is laxer and allows either order.
+    In this syntax, to write anything except a simple integer constant for
+    <replaceable class="parameter">start</> or <replaceable
+    class="parameter">count</replaceable>, you must write parentheses
+    around it.
+    If <replaceable class="parameter">count</> is
+    omitted in a <literal>FETCH</> clause, it defaults to 1.
     <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.  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.
+    the effects of these clauses.
+    According to the standard, the <literal>OFFSET</literal> clause must come
+    before the <literal>FETCH</literal> clause if both are present; but
+    <productname>PostgreSQL</> is laxer and allows either order.
    </para>
 
    <para>
