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Fix some minor grammatical errors.

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This commit is contained in:
Tom Lane 2003-01-12 18:42:59 +00:00
parent 9392c40553
commit b05204ac8a
1 changed files with 4 additions and 4 deletions
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8
doc/src/sgml/perform.sgml
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@ -1,5 +1,5 @@
<!-- <!--
$Header: /cvsroot/pgsql/doc/src/sgml/perform.sgml,v 1.22 2002/11/11 20:14:03 petere Exp $ $Header: /cvsroot/pgsql/doc/src/sgml/perform.sgml,v 1.23 2003/01/12 18:42:59 tgl Exp $
--> -->
<chapter id="performance-tips"> <chapter id="performance-tips">
@ -600,7 +600,7 @@ SELECT * FROM a, b, c WHERE a.id = b.id AND b.ref = c.id;
SELECT * FROM a CROSS JOIN b CROSS JOIN c WHERE a.id = b.id AND b.ref = c.id; SELECT * FROM a CROSS JOIN b CROSS JOIN c WHERE a.id = b.id AND b.ref = c.id;
SELECT * FROM a JOIN (b JOIN c ON (b.ref = c.id)) ON (a.id = b.id); SELECT * FROM a JOIN (b JOIN c ON (b.ref = c.id)) ON (a.id = b.id);
</programlisting> </programlisting>
but the second and third take less time to plan than the first. This effect the second and third take less time to plan than the first. This effect
is not worth worrying about for only three tables, but it can be a is not worth worrying about for only three tables, but it can be a
lifesaver with many tables. lifesaver with many tables.
</para> </para>
@ -628,8 +628,8 @@ SELECT * FROM d LEFT JOIN
(SELECT * FROM a, b, c WHERE ...) AS ss (SELECT * FROM a, b, c WHERE ...) AS ss
ON (...); ON (...);
</programlisting> </programlisting>
Here, joining D must be the last step in the query plan, but the Here, joining to D must be the last step in the query plan, but the
planner is free to consider various join orders for A, B, C. planner is free to consider various join orders for A, B, and C.
</para> </para>
<para> <para>