<para>

When multiple window functions are used, all the window functions having

syntacticallyequivalent <literal>PARTITION BY</literal> and <literal>ORDER BY</literal>

clauses in their window definitions are guaranteed tobe evaluated in a

single pass overthedata. Therefore they will seethesame sort ordering,

even if the <literal>ORDER BY</literal> doesnot uniquely determinean ordering.

equivalent <literal>PARTITION BY</literal> and <literal>ORDER BY</literal>

clauses in their window definitions are guaranteed tosee the same

ordering oftheinput rows, even ifthe<literal>ORDER BY</literal> does

not uniquely determinethe ordering.

However, no guarantees are made about the evaluation of functions having

different <literal>PARTITION BY</literal> or <literal>ORDER BY</literal> specifications.

(In such cases a sort step is typically required between the passes of