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Describe the date/time parsing rules.

Include specific information on the supported time zones.
 It's a really big table, so maybe it should go into an appendix instead.
This commit is contained in:
Thomas G. Lockhart
1999-02-13 03:42:10 +00:00
parent 0c30f18fbe
commit af2a0dfd65

View File

@ -1255,270 +1255,15 @@ the time zone becomes GMT (on most systems anyway).
</thead> </thead>
<tbody> <tbody>
<row> <row>
<entry>ACSST</entry> <entry>NZDT</entry>
<entry>+10:30 </entry> <entry>+13:00</entry>
<entry>Central Australia Summer Std Time</entry> <entry>New Zealand Daylight Time</entry>
</row>
<row>
<entry>ACST</entry>
<entry>+09:30 </entry>
<entry>Central Australia Std Time</entry>
</row>
<row>
<entry>ADT</entry>
<entry>-02:00 </entry>
<entry>Atlantic Daylight Time</entry>
</row>
<row>
<entry>AESST</entry>
<entry>+11:00 </entry>
<entry>Australia Eastern Summer Std Time</entry>
</row>
<row>
<entry>AEST</entry>
<entry>+10:00 </entry>
<entry>Australia Eastern Std Time</entry>
</row>
<row>
<entry>AHST</entry>
<entry>-10:00 </entry>
<entry>Alaska-Hawaii Std Time</entry>
</row>
<row>
<entry>AST</entry>
<entry>-4:00 </entry>
<entry>Atlantic Std Time (Canada)</entry>
</row>
<row>
<entry>AWSST</entry>
<entry>+9:00 </entry>
<entry>Australia Western Summer Std Time</entry>
</row>
<row>
<entry>AWST</entry>
<entry>+8:00 </entry>
<entry>Australia Western Std Time</entry>
</row>
<row>
<entry>BST</entry>
<entry>+1:00 </entry>
<entry>British Summer Time</entry>
</row>
<row>
<entry>BT</entry>
<entry>+3:00 </entry>
<entry>Baghdad Time</entry>
</row>
<row>
<entry>CADT</entry>
<entry>+10:30 </entry>
<entry>Central Australia Daylight Savings Time</entry>
</row>
<row>
<entry>CAST</entry>
<entry>+09:30 </entry>
<entry>Central Australia Std Time</entry>
</row>
<row>
<entry>CAT</entry>
<entry>-10:00 </entry>
<entry>Central Alaska Time</entry>
</row>
<row>
<entry>CCT</entry>
<entry>+8:00 </entry>
<entry>China Coastal Time</entry>
</row>
<row>
<entry>CDT</entry>
<entry>-5:00 </entry>
<entry>Central Daylight Time</entry>
</row>
<row>
<entry>CET</entry>
<entry>+1:00 </entry>
<entry>Central European Time</entry>
</row>
<row>
<entry>CETDST</entry>
<entry>+2:00 </entry>
<entry>Central European Daylight Savings Time</entry>
</row>
<row>
<entry>CST</entry>
<entry>+6:00 </entry>
<entry>Central Std Time</entry>
</row>
<row>
<entry>DNT</entry>
<entry>+1:00 </entry>
<entry>Dansk Normal Tid</entry>
</row>
<row>
<entry>DST</entry>
<entry>+1:00 </entry>
<entry>Dansk Standard Time (?)</entry>
</row>
<row>
<entry>EAST</entry>
<entry>+10:00 </entry>
<entry>East Australian Std Time</entry>
</row>
<row>
<entry>EDT</entry>
<entry>-4:00 </entry>
<entry>Eastern Daylight Time</entry>
</row>
<row>
<entry>EET</entry>
<entry>+2:00 </entry>
<entry>Eastern Europe, USSR Zone 1</entry>
</row>
<row>
<entry>EETDST</entry>
<entry>+3:00 </entry>
<entry>Eastern Europe Daylight Savings Time</entry>
</row>
<row>
<entry>EST</entry>
<entry>-5:00 </entry>
<entry>Eastern Standard Time</entry>
</row>
<row>
<entry>FST</entry>
<entry>+1:00 </entry>
<entry>French Summer Time</entry>
</row>
<row>
<entry>FWT</entry>
<entry>+2:00</entry>
<entry>French Winter Time</entry>
</row>
<row>
<entry>GMT</entry>
<entry>0:00</entry>
<entry>Greenwish Mean Time</entry>
</row>
<row>
<entry>GST</entry>
<entry>+10:00</entry>
<entry>Guam Std Time, USSR Zone 9</entry>
</row>
<row>
<entry>HDT</entry>
<entry>-9:00</entry>
<entry>Hawaii/Alaska</entry>
</row> </row>
<row> <row>
<entry>IDLE</entry> <entry>IDLE</entry>
<entry>+12:00</entry> <entry>+12:00</entry>
<entry>International Date Line, East</entry> <entry>International Date Line, East</entry>
</row> </row>
<row>
<entry>IDLW</entry>
<entry>-12:00</entry>
<entry>International Date Line, West</entry>
</row>
<row>
<entry>IST</entry>
<entry>+2:00</entry>
<entry>Israel</entry>
</row>
<row>
<entry>IT</entry>
<entry>+3:40</entry>
<entry>Iran Time</entry>
</row>
<row>
<entry>JST</entry>
<entry>+9:00</entry>
<entry>Japan Std Time,USSR Zone 8</entry>
</row>
<row>
<entry>JT</entry>
<entry>+7:30</entry>
<entry>Java Time</entry>
</row>
<row>
<entry>KST</entry>
<entry>+9:00</entry>
<entry>Korea Standard Time</entry>
</row>
<row>
<entry>LIGT</entry>
<entry>+10:00</entry>
<entry>Melbourne, Australia</entry>
</row>
<row>
<entry>MDT</entry>
<entry>-6:00</entry>
<entry>Mountain Daylight Time</entry>
</row>
<row>
<entry>MEST</entry>
<entry>+2:00</entry>
<entry>Middle Europe Summer Time</entry>
</row>
<row>
<entry>MET</entry>
<entry>+1:00</entry>
<entry>Middle Europe Time</entry>
</row>
<row>
<entry>METDST</entry>
<entry>+2:00</entry>
<entry>Middle Europe Daylight Time</entry>
</row>
<row>
<entry>MEWT</entry>
<entry>+1:00</entry>
<entry>Middle Europe Winter Time</entry>
</row>
<row>
<entry>MEZ</entry>
<entry>+1:00</entry>
<entry>Middle Europe Zone</entry>
</row>
<row>
<entry>MST</entry>
<entry>-7:00</entry>
<entry>Mountain Standard Time</entry>
</row>
<row>
<entry>MT</entry>
<entry>+8:30</entry>
<entry>Moluccas Time</entry>
</row>
<row>
<entry>NDT</entry>
<entry>-2:30</entry>
<entry>Newfoundland Daylight Time</entry>
</row>
<row>
<entry>NFT</entry>
<entry>-3:30</entry>
<entry>Newfoundland Standard Time</entry>
</row>
<row>
<entry>NOR</entry>
<entry>+1:00</entry>
<entry>Norway Standard Time</entry>
</row>
<row>
<entry>NST</entry>
<entry>-3:30</entry>
<entry>Newfoundland Standard Time</entry>
</row>
<row>
<entry>NT</entry>
<entry>-11:00</entry>
<entry>Nome Time</entry>
</row>
<row>
<entry>NZDT</entry>
<entry>+13:00</entry>
<entry>New Zealand Daylight Time</entry>
</row>
<row> <row>
<entry>NZST</entry> <entry>NZST</entry>
<entry>+12:00</entry> <entry>+12:00</entry>
@ -1529,6 +1274,311 @@ the time zone becomes GMT (on most systems anyway).
<entry>+12:00</entry> <entry>+12:00</entry>
<entry>New Zealand Time</entry> <entry>New Zealand Time</entry>
</row> </row>
<row>
<entry>AESST</entry>
<entry>+11:00 </entry>
<entry>Australia Eastern Summer Std Time</entry>
</row>
<row>
<entry>ACSST</entry>
<entry>+10:30 </entry>
<entry>Central Australia Summer Std Time</entry>
</row>
<row>
<entry>CADT</entry>
<entry>+10:30 </entry>
<entry>Central Australia Daylight Savings Time</entry>
</row>
<row>
<entry>SADT</entry>
<entry>+10:30</entry>
<entry>South Australian Daylight Time</entry>
</row>
<row>
<entry>AEST</entry>
<entry>+10:00 </entry>
<entry>Australia Eastern Std Time</entry>
</row>
<row>
<entry>EAST</entry>
<entry>+10:00 </entry>
<entry>East Australian Std Time</entry>
</row>
<row>
<entry>GST</entry>
<entry>+10:00</entry>
<entry>Guam Std Time, USSR Zone 9</entry>
</row>
<row>
<entry>LIGT</entry>
<entry>+10:00</entry>
<entry>Melbourne, Australia</entry>
</row>
<row>
<entry>ACST</entry>
<entry>+09:30 </entry>
<entry>Central Australia Std Time</entry>
</row>
<row>
<entry>CAST</entry>
<entry>+09:30 </entry>
<entry>Central Australia Std Time</entry>
</row>
<row>
<entry>SAT</entry>
<entry>+9:30</entry>
<entry>South Australian Std Time</entry>
</row>
<row>
<entry>AWSST</entry>
<entry>+9:00 </entry>
<entry>Australia Western Summer Std Time</entry>
</row>
<row>
<entry>JST</entry>
<entry>+9:00</entry>
<entry>Japan Std Time,USSR Zone 8</entry>
</row>
<row>
<entry>KST</entry>
<entry>+9:00</entry>
<entry>Korea Standard Time</entry>
</row>
<row>
<entry>WDT</entry>
<entry>+9:00</entry>
<entry>West Australian Daylight Time</entry>
</row>
<row>
<entry>MT</entry>
<entry>+8:30</entry>
<entry>Moluccas Time</entry>
</row>
<row>
<entry>AWST</entry>
<entry>+8:00 </entry>
<entry>Australia Western Std Time</entry>
</row>
<row>
<entry>CCT</entry>
<entry>+8:00 </entry>
<entry>China Coastal Time</entry>
</row>
<row>
<entry>WADT</entry>
<entry>+8:00</entry>
<entry>West Australian Daylight Time</entry>
</row>
<row>
<entry>WST</entry>
<entry>+8:00</entry>
<entry>West Australian Std Time</entry>
</row>
<row>
<entry>JT</entry>
<entry>+7:30</entry>
<entry>Java Time</entry>
</row>
<row>
<entry>WAST</entry>
<entry>+7:00</entry>
<entry>West Australian Std Time</entry>
</row>
<row>
<entry>IT</entry>
<entry>+3:30</entry>
<entry>Iran Time</entry>
</row>
<row>
<entry>BT</entry>
<entry>+3:00 </entry>
<entry>Baghdad Time</entry>
</row>
<row>
<entry>EETDST</entry>
<entry>+3:00 </entry>
<entry>Eastern Europe Daylight Savings Time</entry>
</row>
<row>
<entry>CETDST</entry>
<entry>+2:00 </entry>
<entry>Central European Daylight Savings Time</entry>
</row>
<row>
<entry>EET</entry>
<entry>+2:00 </entry>
<entry>Eastern Europe, USSR Zone 1</entry>
</row>
<row>
<entry>FWT</entry>
<entry>+2:00</entry>
<entry>French Winter Time</entry>
</row>
<row>
<entry>IST</entry>
<entry>+2:00</entry>
<entry>Israel Std Time</entry>
</row>
<row>
<entry>MEST</entry>
<entry>+2:00</entry>
<entry>Middle Europe Summer Time</entry>
</row>
<row>
<entry>METDST</entry>
<entry>+2:00</entry>
<entry>Middle Europe Daylight Time</entry>
</row>
<row>
<entry>SST</entry>
<entry>+2:00</entry>
<entry>Swedish Summer Time</entry>
</row>
<row>
<entry>BST</entry>
<entry>+1:00 </entry>
<entry>British Summer Time</entry>
</row>
<row>
<entry>CET</entry>
<entry>+1:00 </entry>
<entry>Central European Time</entry>
</row>
<row>
<entry>DNT</entry>
<entry>+1:00 </entry>
<entry>Dansk Normal Tid</entry>
</row>
<row>
<entry>DST</entry>
<entry>+1:00 </entry>
<entry>Dansk Standard Time (?)</entry>
</row>
<row>
<entry>FST</entry>
<entry>+1:00 </entry>
<entry>French Summer Time</entry>
</row>
<row>
<entry>MET</entry>
<entry>+1:00</entry>
<entry>Middle Europe Time</entry>
</row>
<row>
<entry>MEWT</entry>
<entry>+1:00</entry>
<entry>Middle Europe Winter Time</entry>
</row>
<row>
<entry>MEZ</entry>
<entry>+1:00</entry>
<entry>Middle Europe Zone</entry>
</row>
<row>
<entry>NOR</entry>
<entry>+1:00</entry>
<entry>Norway Standard Time</entry>
</row>
<row>
<entry>SET</entry>
<entry>+1:00</entry>
<entry>Seychelles Time</entry>
</row>
<row>
<entry>SWT</entry>
<entry>+1:00</entry>
<entry>Swedish Winter Time</entry>
</row>
<row>
<entry>WETDST</entry>
<entry>+1:00</entry>
<entry>Western Europe Daylight Savings Time</entry>
</row>
<row>
<entry>GMT</entry>
<entry>0:00</entry>
<entry>Greenwish Mean Time</entry>
</row>
<row>
<entry>WET</entry>
<entry>0:00</entry>
<entry>Western Europe</entry>
</row>
<row>
<entry>WAT</entry>
<entry>-1:00</entry>
<entry>West Africa Time</entry>
</row>
<row>
<entry>NDT</entry>
<entry>-2:30</entry>
<entry>Newfoundland Daylight Time</entry>
</row>
<row>
<entry>ADT</entry>
<entry>-03:00 </entry>
<entry>Atlantic Daylight Time</entry>
</row>
<row>
<entry>NFT</entry>
<entry>-3:30</entry>
<entry>Newfoundland Standard Time</entry>
</row>
<row>
<entry>NST</entry>
<entry>-3:30</entry>
<entry>Newfoundland Standard Time</entry>
</row>
<row>
<entry>AST</entry>
<entry>-4:00 </entry>
<entry>Atlantic Std Time (Canada)</entry>
</row>
<row>
<entry>EDT</entry>
<entry>-4:00 </entry>
<entry>Eastern Daylight Time</entry>
</row>
<row>
<entry>ZP4</entry>
<entry>-4:00</entry>
<entry>GMT +4 hours</entry>
</row>
<row>
<entry>CDT</entry>
<entry>-5:00 </entry>
<entry>Central Daylight Time</entry>
</row>
<row>
<entry>EST</entry>
<entry>-5:00 </entry>
<entry>Eastern Standard Time</entry>
</row>
<row>
<entry>ZP5</entry>
<entry>-5:00</entry>
<entry>GMT +5 hours</entry>
</row>
<row>
<entry>CST</entry>
<entry>-6:00 </entry>
<entry>Central Std Time</entry>
</row>
<row>
<entry>MDT</entry>
<entry>-6:00</entry>
<entry>Mountain Daylight Time</entry>
</row>
<row>
<entry>ZP6</entry>
<entry>-6:00</entry>
<entry>GMT +6 hours</entry>
</row>
<row>
<entry>MST</entry>
<entry>-7:00</entry>
<entry>Mountain Standard Time</entry>
</row>
<row> <row>
<entry>PDT</entry> <entry>PDT</entry>
<entry>-7:00</entry> <entry>-7:00</entry>
@ -1539,90 +1589,40 @@ the time zone becomes GMT (on most systems anyway).
<entry>-8:00</entry> <entry>-8:00</entry>
<entry>Pacific Std Time</entry> <entry>Pacific Std Time</entry>
</row> </row>
<row>
<entry>SADT</entry>
<entry>+10:30</entry>
<entry>South Australian Daylight Time</entry>
</row>
<row>
<entry>SAT</entry>
<entry>+9:30</entry>
<entry>South Australian Std Time</entry>
</row>
<row>
<entry>SET</entry>
<entry>+1:00</entry>
<entry>Seychelles Time</entry>
</row>
<row>
<entry>SST</entry>
<entry>+2:00</entry>
<entry>Swedish Summer Time</entry>
</row>
<row>
<entry>SWT</entry>
<entry>+1:00</entry>
<entry>Swedish Winter Time</entry>
</row>
<row>
<entry>WADT</entry>
<entry>+8:00</entry>
<entry>West Australian Daylight Time</entry>
</row>
<row>
<entry>WAST</entry>
<entry>+7:00</entry>
<entry>West Australian Std Time</entry>
</row>
<row>
<entry>WAT</entry>
<entry>-1:00</entry>
<entry>West Africa Time</entry>
</row>
<row>
<entry>WDT</entry>
<entry>+9:00</entry>
<entry>West Australian Daylight Time</entry>
</row>
<row>
<entry>WET</entry>
<entry>0:00</entry>
<entry>Western Europe</entry>
</row>
<row>
<entry>WETDST</entry>
<entry>+1:00</entry>
<entry>Western Europe Daylight Savings Time</entry>
</row>
<row>
<entry>WST</entry>
<entry>+8:00</entry>
<entry>West Australian Std Time</entry>
</row>
<row> <row>
<entry>YDT</entry> <entry>YDT</entry>
<entry>-8:00</entry> <entry>-8:00</entry>
<entry>Yukon Daylight Time</entry> <entry>Yukon Daylight Time</entry>
</row> </row>
<row>
<entry>HDT</entry>
<entry>-9:00</entry>
<entry>Hawaii/Alaska Daylight Time</entry>
</row>
<row> <row>
<entry>YST</entry> <entry>YST</entry>
<entry>-9:00</entry> <entry>-9:00</entry>
<entry>Yukon Standard Time</entry> <entry>Yukon Standard Time</entry>
</row> </row>
<row> <row>
<entry>ZP4</entry> <entry>AHST</entry>
<entry>-4:00</entry> <entry>-10:00 </entry>
<entry>GMT +4 hours</entry> <entry>Alaska-Hawaii Std Time</entry>
</row> </row>
<row> <row>
<entry>ZP5</entry> <entry>CAT</entry>
<entry>-5:00</entry> <entry>-10:00 </entry>
<entry>GMT +5 hours</entry> <entry>Central Alaska Time</entry>
</row> </row>
<row> <row>
<entry>ZP6</entry> <entry>NT</entry>
<entry>-6:00</entry> <entry>-11:00</entry>
<entry>GMT +6 hours</entry> <entry>Nome Time</entry>
</row>
<row>
<entry>IDLW</entry>
<entry>-12:00</entry>
<entry>International Date Line, West</entry>
</row> </row>
</tbody> </tbody>
</tgroup> </tgroup>
@ -1633,17 +1633,21 @@ the time zone becomes GMT (on most systems anyway).
then <literal>EST</literal> refers to Australia Eastern Std Time, then <literal>EST</literal> refers to Australia Eastern Std Time,
which has an offset of +10:00 hours from UTC. which has an offset of +10:00 hours from UTC.
</para> </para>
</note>
<para> <para>
It is interesting that Australian time zones and their naming variants Australian time zones and their naming variants
account for fully one quarter of all time zones in the account for fully one quarter of all time zones in the
<productname>Postgres</productname> time zone lookup table. <productname>Postgres</productname> time zone lookup table.
</para> </para>
</note>
</para>
<procedure> <procedure>
<title>Date/Time Input Interpretation</title> <title>Date/Time Input Interpretation</title>
<para>
The date/time types are all decoded using a common set of routines.
</para>
<step> <step>
<para> <para>
Break the input string into tokens and categorize each token as Break the input string into tokens and categorize each token as
@ -1717,40 +1721,81 @@ the time zone becomes GMT (on most systems anyway).
<step> <step>
<para> <para>
The token is a number or number field. If there are more than 4 digits, The token is a number or number field.
If there are more than 4 digits,
and if no other date fields have been previously read, then interpret and if no other date fields have been previously read, then interpret
as a "concatenated date". as a "concatenated date" (e.g. <literal>19990118</literal>).
</para> </para>
<substeps> <substeps>
<step> <step>
<para>If there </para> <para>
If there are more than 4 digits,
and if no other date fields have been previously read, then interpret
as a "concatenated date" (e.g. <literal>19990118</literal>).
</para>
</step>
<step>
<para>
If three digits and a year has already been decoded, then interpret as day of year.
</para>
</step>
<step>
<para>
If longer than two digits, then interpret as a year.
</para>
</step>
<step>
<para>
If in European date mode, and if the day field has not yet been read,
and if the value is less than or equal to 31, then interpret as a day.
</para>
</step>
<step>
<para>
If in non-European (US) date mode, and if the month field has not yet been read,
and if the value is less than or equal to 12, then interpret as a month.
</para>
</step>
<step>
<para>
If the day field has not yet been read,
and if the value is less than or equal to 31, then interpret as a month.
</para>
</step>
<step>
<para>
If the month field has not yet been read,
and if the value is less than or equal to 12, then interpret as a month.
</para>
</step>
<step>
<para>
Otherwise, interpret as a year.
</para>
</step> </step>
</substeps> </substeps>
</step> </step>
<step> <step>
<para> <para>
If BC has been specified, negate the year and offset by one
(there is no year zero in the Gregorian calendar).
</para> </para>
</step> </step>
<step> <step>
<para> <para>
</para> If BC was not specified, and if the year field was two digits in length, then
</step> adjust the year to 4 digits. If the field was less than 70, then add 2000;
otherwise, add 1900.
<step>
<para>
</para>
</step>
<step>
<para>
</para>
</step>
<step>
<para>
</para> </para>
</step> </step>
@ -2377,7 +2422,7 @@ the bits part.
<!-- Keep this comment at the end of the file <!-- Keep this comment at the end of the file
Local variables: Local variables:
mode: sgml mode: sgml
sgml-omittag:t sgml-omittag:nil
sgml-shorttag:t sgml-shorttag:t
sgml-minimize-attributes:nil sgml-minimize-attributes:nil
sgml-always-quote-attributes:t sgml-always-quote-attributes:t