Mention paremeterized queries do not work with partial indexes.

Simon Riggs
This commit is contained in:
Bruce Momjian 2006-09-04 19:58:02 +00:00
parent 497f49a736
commit a65f7db3b5

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@ -1,4 +1,4 @@
<!-- $PostgreSQL: pgsql/doc/src/sgml/indices.sgml,v 1.58 2006/08/25 04:06:44 tgl Exp $ -->
<!-- $PostgreSQL: pgsql/doc/src/sgml/indices.sgml,v 1.59 2006/09/04 19:58:02 momjian Exp $ -->
<chapter id="indexes">
<title id="indexes-title">Indexes</title>
@ -679,7 +679,12 @@ SELECT * FROM orders WHERE order_nr = 3501;
<quote>x &lt; 1</quote> implies <quote>x &lt; 2</quote>; otherwise
the predicate condition must exactly match part of the query's
<literal>WHERE</> condition
or the index will not be recognized to be usable.
or the index will not be recognized to be usable. Matching takes
place at query planning time, not at run time. As a result,
parameterized query clauses will not work with a partial index. For
example a prepared query with a parameter might specify
<quote>x &lt; ?</quote> which will never imply
<quote>x &lt; 2</quote> for all possible values of the parameter.
</para>
<para>