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Improve documentation for CREATE CONSTRAINT TRIGGER.
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‎doc/src/sgml/ref/create_constraint.sgml

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<!--
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$PostgreSQL: pgsql/doc/src/sgml/ref/create_constraint.sgml,v 1.17 2006/10/17 12:53:03 momjian Exp $
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$PostgreSQL: pgsql/doc/src/sgml/ref/create_constraint.sgml,v 1.18 2007/02/10 20:43:59 tgl Exp $
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PostgreSQL documentation
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-->
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@@ -15,13 +15,13 @@ PostgreSQL documentation
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</refnamediv>
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<indexterm zone="sql-createconstraint">
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<primary>CREATE CONSTRAINT</primary>
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<primary>CREATE CONSTRAINT TRIGGER</primary>
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</indexterm>
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<refsynopsisdiv>
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<synopsis>
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CREATE CONSTRAINT TRIGGER <replaceable class="parameter">name</replaceable>
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AFTER <replaceable class="parameter">event [ OR ... ]</replaceable>
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AFTER <replaceable class="parameter">event</replaceable> [ OR ... ]
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ON <replaceable class="parameter">table_name</replaceable>
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[ FROM <replaceable class="parameter">referenced_table_name</replaceable> ]
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{ NOT DEFERRABLE | [ DEFERRABLE ] { INITIALLY IMMEDIATE | INITIALLY DEFERRED } }
@@ -34,27 +34,30 @@ CREATE CONSTRAINT TRIGGER <replaceable class="parameter">name</replaceable>
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<title>Description</title>
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<para>
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<command>CREATE CONSTRAINT TRIGGER</command> is used within
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<command>CREATE TABLE</command>/<command>ALTER TABLE</command> and by
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<application>pg_dump</application> to create the special triggers for
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referential integrity.
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It is not intended for general use.
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</para>
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</refsect1>
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<command>CREATE CONSTRAINT TRIGGER</command> creates a
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<firstterm>constraint trigger</>. This is the same as a regular trigger
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except that the timing of the trigger firing can be adjusted using
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<xref linkend="SQL-SET-CONSTRAINTS" endterm="SQL-SET-CONSTRAINTS-TITLE">.
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Constraint triggers must be <literal>AFTER ROW</> triggers. They can
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be fired either at the end of the statement causing the triggering event,
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or at the end of the containing transaction; in the latter case they are
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said to be <firstterm>deferred</>. A pending deferred-trigger firing can
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also be forced to happen immediately by using <command>SET CONSTRAINTS</>.
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</para>
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</refsect1>
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<refsect1>
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<refsect1>
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<title>Parameters</title>
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<variablelist>
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<varlistentry>
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<term><replaceable class="PARAMETER">name</replaceable></term>
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<listitem>
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<para>
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The name of the constraint trigger. The actual name of the
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created trigger will be of the form
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<literal>RI_ConstraintTrigger_0000</literal> (where 0000 is some number
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assigned by the server).
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Use this assigned name when dropping the trigger.
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The name of the constraint trigger. This is also the name to use
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when modifying the trigger's behavior using <command>SET CONSTRAINTS</>.
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The name cannot be schema-qualified &mdash; the trigger inherits the
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schema of its table.
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</para>
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</listitem>
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</varlistentry>
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<term><replaceable class="PARAMETER">referenced_table_name</replaceable></term>
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<listitem>
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<para>
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The (possibly schema-qualified) name of the table referenced by the
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constraint. Used by foreign key constraints triggers.
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The (possibly schema-qualified) name of another table referenced by the
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constraint. This option is used for foreign-key constraints and is not
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recommended for general use.
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</para>
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</listitem>
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</varlistentry>
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<term><literal>INITIALLY DEFERRED</literal></term>
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<listitem>
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<para>
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The default timing of the trigger.
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See the <xref linkend="SQL-CREATETABLE" endterm="SQL-CREATETABLE-TITLE">
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documentation for details of these constraint options.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><replaceable class="PARAMETER">funcname</replaceable>(<replaceable class="PARAMETER">args</replaceable>)</term>
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<term><replaceable class="PARAMETER">funcname</replaceable></term>
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<listitem>
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<para>
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The function to call as part of the trigger processing. See <xref
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The function to call when the trigger is fired. See <xref
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linkend="SQL-CREATETRIGGER" endterm="SQL-CREATETRIGGER-TITLE"> for
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details.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><replaceable class="PARAMETER">arguments</replaceable></term>
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<listitem>
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<para>
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Optional argument strings to pass to the trigger function. See <xref
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linkend="SQL-CREATETRIGGER" endterm="SQL-CREATETRIGGER-TITLE"> for
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details.
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</para>
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<refsect1>
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<title>Compatibility</title>
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<para>
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<command>CREATE CONTRAINT TRIGGER</command> is a
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<command>CREATE CONSTRAINT TRIGGER</command> is a
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<productname>PostgreSQL</productname> extension of the <acronym>SQL</>
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standard.
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</para>
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</refsect1>
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</refentry>
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<refsect1>
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<title>See Also</title>
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<simplelist type="inline">
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<member><xref linkend="sql-createtrigger" endterm="sql-createtrigger-title"></member>
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<member><xref linkend="sql-droptrigger" endterm="sql-droptrigger-title"></member>
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<member><xref linkend="sql-set-constraints" endterm="sql-set-constraints-title"></member>
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</simplelist>
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</refsect1>
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</refentry>

‎doc/src/sgml/ref/set_constraints.sgml

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<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/set_constraints.sgml,v 1.14 2006/09/16 00:30:20 momjian Exp $ -->
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<!-- $PostgreSQL: pgsql/doc/src/sgml/ref/set_constraints.sgml,v 1.15 2007/02/10 20:43:59 tgl Exp $ -->
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<refentry id="SQL-SET-CONSTRAINTS">
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<refmeta>
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<refentrytitle id="SQL-SET-CONSTRAINTS-title">SET CONSTRAINTS</refentrytitle>
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<para>
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Currently, only foreign key constraints are affected by this
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setting. Check and unique constraints are always effectively
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not deferrable.
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not deferrable. Triggers that are declared as <quote>constraint
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triggers</> are also affected.
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</para>
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</refsect1>
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