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-$PostgreSQL: pgsql/doc/src/sgml/datatype.sgml,v 1.153 2005/01/08 05:19:18 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/datatype.sgml,v 1.154 2005/01/17 18:47:15 tgl Exp $
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<chapter id="datatype">
<entry>time intervals</entry>
<entry>-178000000 years</entry>
<entry>178000000 years</entry>
- <entry>1 microsecond</entry>
+ <entry>1 microsecond / 14 digits</entry>
</row>
<row>
<entry><type>date</type></entry>
<entry>times of day only</entry>
<entry>00:00:00.00</entry>
<entry>23:59:59.99</entry>
- <entry>1 microsecond</entry>
+ <entry>1 microsecond / 14 digits</entry>
</row>
<row>
<entry><type>time [ (<replaceable>p</replaceable>) ] with time zone</type></entry>
<entry>times of day only, with time zone</entry>
<entry>00:00:00.00+12</entry>
<entry>23:59:59.99-12</entry>
- <entry>1 microsecond</entry>
+ <entry>1 microsecond / 14 digits</entry>
</row>
</tbody>
</tgroup>
eight-byte integers (a compile-time
option), microsecond precision is available over the full range of
values. However eight-byte integer timestamps have a more limited range of
- dates than shown above: from 4713 BC up to 294276 AD.
+ dates than shown above: from 4713 BC up to 294276 AD. The same
+ compile-time option also determines whether <type>time</type> and
+ <type>interval</type> values are stored as floating-point or eight-byte
+ integers. In the floating-point case, large <type>interval</type> values
+ degrade in precision as the size of the interval increases.
</para>
</note>