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<chapter id="datatype">

<entry><type>time [ (<replaceable>p</replaceable>) ] [ without time zone ]</type></entry>

<entry>8 bytes</entry>

<entry>times of day only</entry>

<entry>00:00:00.00</entry>

<entry>00:00:00</entry>

<entry>24:00:00</entry>

<entry>1 microsecond / 14 digits</entry>

</row>

<row>

<entry><type>time [ (<replaceable>p</replaceable>) ] with time zone</type></entry>

<entry>12 bytes</entry>

<entry>times of day only, with time zone</entry>

<entry>00:00:00.00+12</entry>

<entry>24:00:00-12</entry>

<entry>00:00:00+1359</entry>

<entry>24:00:00-1359</entry>

<entry>1 microsecond / 14 digits</entry>

</row>

</tbody>

<para>

The <acronym>SQL</acronym> standard differentiates <type>timestamp without time zone</type>

and <type>timestamp with time zone</type> literals by theexistence of a

<quote>+</quote>; or <quote>-</quote>. Hence, according to the standard,

and <type>timestamp with time zone</type> literals by thepresence of a

<quote>+</quote> or <quote>-</quote>. Hence, according to the standard,

<programlisting>TIMESTAMP '2004-10-19 10:23:54'</programlisting>

is a <type>timestamp without time zone</type>, while

<programlisting>TIMESTAMP '2004-10-19 10:23:54+02'</programlisting>

is a <type>timestamp with time zone</type>.

<productname>PostgreSQL</productname>

differs from the standard by requiring that <type>timestamp with time zone</type>

literals be explicitly typed:

<productname>PostgreSQL</productname> never examines the content of a

literal string before determining its type, and therefore will treat

both of the above as <type>timestamp without time zone</type>. To

ensure that a literal is treated as <type>timestamp with time

zone</type>, give it the correct explicit type:

<programlisting>TIMESTAMP WITH TIME ZONE '2004-10-19 10:23:54+02'</programlisting>

If a literal is not explicitly indicated as being of <type>timestamp with time zone</type>,

<productname>PostgreSQL</productname> will silently ignore any time zone indication in the literal.

That is, the resulting date/time value is derived from the date/time

In a literal that has been decided to be <type>timestamp without time

zone</type>, <productname>PostgreSQL</productname> will silently ignore

any time zone indication.

That is, the resulting value is derived from the date/time

fields in the input value, and is not adjusted for time zone.

</para>