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@ -1,5 +1,5 @@ |
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<!-- |
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$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_table.sgml,v 1.21 2000/04/12 04:40:03 thomas Exp $ |
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$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_table.sgml,v 1.22 2000/04/13 07:19:27 momjian Exp $ |
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Postgres documentation |
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--> |
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@ -393,21 +393,6 @@ DEFAULT <replaceable class="PARAMETER">value</replaceable> |
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</variablelist> |
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</para> |
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<para> |
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In the current release (v7.0), <productname>Postgres</productname> |
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evaluates all default expressions at the time the table is defined. |
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Hence, functions which are "non-cacheable" such as |
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<function>CURRENT_TIMESTAMP</function> may not produce the desired |
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effect. For the particular case of date/time types, one can work |
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around this behavior by using |
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<quote>DEFAULT TEXT 'now'</quote> |
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instead of |
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<quote>DEFAULT 'now'</quote> |
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or |
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<quote>DEFAULT CURRENT_TIMESTAMP</quote>. |
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This forces <productname>Postgres</productname> to consider the constant a string |
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type and then to convert the value to <type>timestamp</type> at runtime. |
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</para> |
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</refsect2> |
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<refsect2 id="R2-SQL-DEFAULTCLAUSE-4"> |
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<title> |
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