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<sect1 id="release-9-0">

<title>Release 9.0</title>

<listitem>

<para>

<link linkend="SQL-CREATETABLE-compatibility">Deferrable

unique constraints. Mass updates to unique keys are now possible

without trickery.</link>

unique constraints</link>. Mass updates to unique keys are now possible

without trickery.

</para>

</listitem>