<!--

$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.78 2001/12/08 03:24:22 thomas Exp $

$Header: /cvsroot/pgsql/doc/src/sgml/datatype.sgml,v 1.79 2001/12/21 03:54:02 thomas Exp $

-->

<chapter id="datatype">

<para>

<type>time</type> and <type>timestamp</type> both accept an

option precision field <replaceable>p</replaceable> which

optional precision field <replaceable>p</replaceable> which

determines the number of digits retained beyond the seconds

decimal point. By default, there is no explicit bound on precision

and the actual precision is determined by the underlying double

precision floating point number used to store values in seconds

for <type>interval</type> and

since 2000-01-01in the case of <type>timestamp</type>.

in secondssince 2000-01-01for <type>timestamp</type>.

</para>

<para>

Time zones, and time-zone conventions, are influenced by

political decisions, not just physical effects. Time zones have

become somewhat standardized around the world during the 1900's,

but continue to

be prone to arbitrary changes.

political decisions, not just geometry. Time zones around the

world became somewhat standardized during the 1900's,

but continue to be prone to arbitrary changes.

<productname>PostgreSQL</productname> uses your operating

system's underlying features to provide time-zone

support, and these systems usually contain information for only

</para>

<para>

To ensure compatibility to earlier versions of <productname>PostgreSQL</productname>

To ensure compatibility to earlier versions of

<productname>PostgreSQL</productname>

we continue to provide <type>datetime</type>

(equivalent to <type>timestamp</type>) and

<type>timespan</type> (equivalent to <type>interval</type>),

however support for these is now restricted to having an

implicit translation to <type>timestamp</type> and

<type>interval</type>.

<type>interval</type>, and these name mappings will be removed in

the next version.

The types <type>abstime</type>

and <type>reltime</type> are lower precision types which are used internally.

You are discouraged from using any of these types in new

Date and time input is accepted in almost any reasonable format, including

<acronym>ISO 8601</acronym>, <acronym>SQL</acronym>-compatible,

traditional <productname>PostgreSQL</productname>, and others.

The ordering of month and day in date input can be ambiguous, therefore a setting

exists to specify how it should be interpreted in ambiguous cases. The command

<literal>SET DateStyle TO 'US'</literal> or <literal>SET DateStyle TO 'NonEuropean'</literal>

For some formats, ordering of month and day in date input can be

ambiguous and there is support for specifying the expected

ordering of these fields.

The command

<literal>SET DateStyle TO 'US'</literal>

or <literal>SET DateStyle TO 'NonEuropean'</literal>

specifies the variant <quote>month before day</quote>, the command

<literal>SET DateStyle TO 'European'</literal> sets the variant

<quote>day before month</quote>. The <literal>ISO</literal> style

is the default but this default can be changed at compile time or at run time.

</para>

<para>

<productname>PostgreSQL</productname> is more flexible in

handling date/time than the

<acronym>SQL</acronym> standard requires.

See <xref linkend="datetime-appendix">

for the exact parsing rules of date/time input and for the recognized time zones.

for the exact parsing rules of date/time input and for the

recognized time zones.

</para>

<para>

Remember that any date or time input needs to be enclosed into

single quotes, like text strings. Refer to <xref

linkend="sql-syntax-constants-generic"> for more information.

Remember that any date or time literal input needs to be enclosed

in single quotes, like text strings. Refer to

<xref linkend="sql-syntax-constants-generic"> for more

information.

<acronym>SQL9x</acronym> requires the following syntax

<synopsis>

<replaceable>type</replaceable> [ (<replaceable>p</replaceable>) ] '<replaceable>value</replaceable>'

</synopsis>

where <replaceable>p</replaceable>is an integer specifying the

handling date/time than the

<acronym>SQL</acronym> standard requires.

where <replaceable>p</replaceable>in the optional precision

for <type>time</type>, <type>timestamp</type>, and

<type>interval</type> types.

</para>

<sect3>

<!-- $Header: /cvsroot/pgsql/doc/src/sgml/installation.sgml,v 1.70 2001/12/19 18:49:56 petere Exp $ -->

<!-- $Header: /cvsroot/pgsql/doc/src/sgml/installation.sgml,v 1.71 2001/12/21 03:54:02 thomas Exp $ -->

<chapter id="installation">

<title><![%standalone-include[<productname>PostgreSQL</>]]>

<entry><systemitem class="osname">AIX</></entry>

<entry><systemitem>RS6000</></entry>

<entry>7.2</entry>

<entry>2001-11-28,

Andreas Zeugswetter (<email>ZeugswetterA@spardat.at</email>)</entry>

<entry>4.3; see also <filename>doc/FAQ_AIX</filename></entry>

<entry>2001-12-19,

Andreas Zeugswetter (<email>ZeugswetterA@spardat.at</email>),

Tatsuo Ishii (<email>t-ishii@sra.co.jp</email>)</entry>

<entry>see also <filename>doc/FAQ_AIX</filename></entry>

</row>

<row>

<entry><systemitem class="osname">BeOS</></entry>

Bruce Momjian (<email>pgman@candle.pha.pa.us</email>)</entry>

<entry>4.2</entry>

</row>

<row>

<entry><systemitem class="osname">FreeBSD</></entry>

<entry><systemitem>Alpha</></entry>

<entry>7.2</entry>

<entry>2001-12-18,

Chris Kings-Lynne (<email>chriskl@familyhealth.com.au</email>)</entry>

<entry></entry>

</row>

<row>

<entry><systemitem class="osname">FreeBSD</></entry>

<entry><systemitem>x86</></entry>

<row>

<entry><systemitem class="osname">Linux</></entry>

<entry><systemitem>armv4l</></entry>

<entry>7.1</entry>

<entry>2001-02-22,

Mark Knox (<email>markk@pixin.net</email>)</entry>

<entry>7.2</entry>

<entry>2001-12-10,

Mark Knox (<email>segfault@hardline.org</email>)</entry>

<entry>2.2.x</entry>

</row>

<row>

Hisao Shibuya (<email>shibuya@alpha.or.jp</>)</entry>

<entry>2.0.x; <productname>Cobalt Qube2</></entry>

</row>

<row>

<entry><systemitem class="osname">Linux</></entry>

<entry><systemitem>PlayStation2</></entry>

<entry>7.2</entry>

<entry>2001-12-12,

Permaine Cheung <email>pcheung@redhat.com</email>)</entry>

<entry>#undef HAS_TEST_AND_SET, slock_t</entry>

</row>

<row>

<entry><systemitem class="osname">Linux</></entry>

<entry><systemitem>PPC74xx</></entry>

<row>

<entry><systemitem class="osname">Linux</></entry>

<entry><systemitem>S/390</></entry>

<entry>7.1</entry>

<entry>2000-11-17,

Neale Ferguson (<email>Neale.Ferguson@softwareAG-usa.com</email>)</entry>

<entry>7.2</entry>

<entry>2001-12-12,

Permaine Cheung<email>pcheung@redhat.com</email>)</entry>

<entry></entry>

</row>

<row>

<row>

<entry><systemitem class="osname">QNX 4.25</></entry>

<entry><systemitem>x86</></entry>

<entry>7.1</entry>

<entry>2001-05-24,

<entry>7.2</entry>

<entry>2001-12-10,

Bernd Tegge (<email>tegge@repas-aeg.de</email>)

</entry>

<entry>see also <filename>doc/FAQ_QNX4</filename></entry>

</row>

<row>

<entry><systemitem class="osname">QNX 6</></entry>

<entry><systemitem>x86</></entry>

<entry>7.2</entry>

<entry>2001-12-10,

Igor Kovalenko (<email>Igor.Kovalenko@motorola.com</email>)

</entry>

<entry>Requires patches for Posix semaphores; see archives</entry>

</row>

<row>

<entry><systemitem class="osname">Solaris</></entry>

Martin Renters (<email>martin@datafax.com</email>)</entry>

<entry>2.8; see also <filename>doc/FAQ_Solaris</filename></entry>

</row>

<row>

<entry><systemitem class="osname">SunOS</></entry>

<entry><systemitem>Sparc</></entry>

<entry>7.2</entry>

<entry>2001-12-04, Tatsuo Ishii (<email>t-ishii@sra.co.jp</email>)</entry>

<entry></entry>

</row>

<row>

<entry><systemitem class="osname">Tru64 UNIX</></entry>

<entry><systemitem>Alpha</></entry>

<entry>7.2</entry>

<entry>2001-11-26,

Alessio Bragadini (<email>alessio@albourne.com</email>)</entry>

<entry>4.0g, with cc and gcc</entry>

Alessio Bragadini (<email>alessio@albourne.com</email>),

Bernd Tegge (<email>tegge@repas-aeg.de</email>)</entry>

<entry>5.0; 4.0g with cc and gcc</entry>

</row>

<row>

<entry><systemitem class="osname">Windows NT/2000</></entry>

<entry><systemitem class="osname">Windows</></entry>

<entry><systemitem>x86</></entry>

<entry>7.1</entry>

<entry>2001-03-16,

<entry>7.2</entry>

<entry>2001-12-13,

Dave Page (<email>dpage@vale-housing.co.uk</email>),

Jason Tishler (<email>jason@tishler.net</email>)</entry>

<entry>with <application>Cygwin</application> tool set, see <filename>doc/FAQ_MSWIN</filename></entry>

<entry>with <application>Cygwin</application>; see <filename>doc/FAQ_MSWIN</filename></entry>

</row>

<row>

<entry><systemitem class="osname">Windows</></entry>

<entry><systemitem>x86</></entry>

<entry>7.2</entry>

<entry>2001-12-10,

Dave Page (<email>dpage@vale-housing.co.uk</email>)</entry>

<entry>

native is client-side only;

<![%standalone-include[see Administrator's Guide]]>

<![%standalone-ignore[see <xref linkend="install-win32">]]>

</entry>

</row>

</tbody>

</tgroup>

</informaltable>

<entry><systemitem>x86</></entry>

<entry>6.5</entry>

<entry>1999-05-25, Andrew Merrill (<email>andrew@compclass.com</>)</entry>

<entry>7.2 should work, but no reports; see also <filename>doc/FAQ_SCO</filename></entry>

</row>

<row>

<entry><systemitem class="osname">SunOS</></entry>

<entry><systemitem>Sparc</></entry>

<entry>7.2</entry>

<entry>2001-12-04, Tatsuo Ishii (<email>t-ishii@sra.co.jp</email>)</entry>

<entry><function>memcmp()</> does not work correctly, so probably not reliable</entry>

<entry>&version; should work, but no reports; see also <filename>doc/FAQ_SCO</filename></entry>

</row>

<row>

<entry><systemitem class="osname">System V R4</></entry>

<entry><systemitem>VAX</></entry>

<entry>6.x</entry>

<entry>1998-03-01</entry>

<entry>no recent reports</entry>

</row>

<row>

<entry><systemitem class="osname">Windows 9x, ME, NT, 2000</> (native)</entry>

<entry><systemitem>x86</></entry>

<entry>7.1</entry>

<entry>2001-03-26, Magnus Hagander (<email>mha@sollentuna.net</email>)</entry>

<entry>

client-side libraries (<application>libpq</> and <application>psql</>) or ODBC or JDBC, no server-side;

<![%standalone-include[see <citetitle>Administrator's Guide</>]]>

<![%standalone-ignore[see <xref linkend="install-win32">]]>

for instructions

</entry>

<entry></entry>

</row>

</tbody>

</tgroup>

</informaltable>

</sect1>

</chapter>