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Fix broken markup and spelling, put paragraph in a somewhat less random

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place.
This commit is contained in:
Tom Lane 2005-07-30 22:53:15 +00:00
parent a42407c5a2
commit ecf7fccebc
1 changed files with 25 additions and 25 deletions
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38
doc/src/sgml/func.sgml
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@ -1,5 +1,5 @@
<!--
$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.274 2005/07/30 14:52:04 momjian Exp $
$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.275 2005/07/30 22:53:15 tgl Exp $
PostgreSQL documentation
-->
@ -4903,24 +4903,6 @@ SELECT SUBSTRING('XY1234Z', 'Y*?([0-9]{1,3})');
such pair.
</para>
<para>
When adding an <type>interval</type> value to (or subtracting an
<type>interval</type> value from) a <type>timestamp with time zone</type>
value, the days component advances (or decrements) the date of the
<type>timestamp with time zone<type> by the indicated number of days.
Across daylight saving time changes (with the session tiem zone set to a
time zone that recognizes DST), this means <literal>interval '1 day'</literal>
does not necessarily equal <literal>interval '24 hours'</literal>.
For example, with the session time zone set to <literal>CST7CDT</literal>
<literal>timestamp with time zone '2005-04-02 12:00-07' + interval '1 day' </literal>
will produce <literal>timestamp with time zone '2005-04-03 12:00-06'</literal>,
while adding <literal>interval '24 hours'</literal> to the same initial
<type>timestamp with time zone</type> produces
<literal>timestamp with time zone '2005-04-03 13:00-06'</literal>, as there is
a change in daylight saving time at <literal>2005-04-03 02:00</literal> in time zone
<literal>CST7CDT</literal>.
</para>
<table id="operators-datetime-table">
<title>Date/Time Operators</title>
@ -5241,6 +5223,24 @@ SELECT (DATE '2001-02-16', INTERVAL '100 days') OVERLAPS
<lineannotation>Result: </lineannotation><computeroutput>false</computeroutput>
</screen>
<para>
When adding an <type>interval</type> value to (or subtracting an
<type>interval</type> value from) a <type>timestamp with time zone</type>
value, the days component advances (or decrements) the date of the
<type>timestamp with time zone</type> by the indicated number of days.
Across daylight saving time changes (with the session time zone set to a
time zone that recognizes DST), this means <literal>interval '1 day'</literal>
does not necessarily equal <literal>interval '24 hours'</literal>.
For example, with the session time zone set to <literal>CST7CDT</literal>,
<literal>timestamp with time zone '2005-04-02 12:00-07' + interval '1 day' </literal>
will produce <literal>timestamp with time zone '2005-04-03 12:00-06'</literal>,
while adding <literal>interval '24 hours'</literal> to the same initial
<type>timestamp with time zone</type> produces
<literal>timestamp with time zone '2005-04-03 13:00-06'</literal>, as there is
a change in daylight saving time at <literal>2005-04-03 02:00</literal> in time zone
<literal>CST7CDT</literal>.
</para>
<sect2 id="functions-datetime-extract">
<title><function>EXTRACT</function>, <function>date_part</function></title>