Merge docs for CREATE CONSTRAINT TRIGGER and CREATE TRIGGER
This commit is contained in:
Alvaro Herrera
parent
0de92fd13c
commit
b47953f9c6
@ -46,7 +46,6 @@ Complete list of usable sgml source files in this directory.
|
||||
<!entity copyTable system "copy.sgml">
|
||||
<!entity createAggregate system "create_aggregate.sgml">
|
||||
<!entity createCast system "create_cast.sgml">
|
||||
<!entity createConstraint system "create_constraint.sgml">
|
||||
<!entity createConversion system "create_conversion.sgml">
|
||||
<!entity createDatabase system "create_database.sgml">
|
||||
<!entity createDomain system "create_domain.sgml">
|
||||
|
||||
@ -1,171 +0,0 @@
|
||||
<!--
|
||||
doc/src/sgml/ref/create_constraint.sgml
|
||||
PostgreSQL documentation
|
||||
-->
|
||||
|
||||
<refentry id="SQL-CREATECONSTRAINT">
|
||||
<refmeta>
|
||||
<refentrytitle>CREATE CONSTRAINT TRIGGER</refentrytitle>
|
||||
<manvolnum>7</manvolnum>
|
||||
<refmiscinfo>SQL - Language Statements</refmiscinfo>
|
||||
</refmeta>
|
||||
|
||||
<refnamediv>
|
||||
<refname>CREATE CONSTRAINT TRIGGER</refname>
|
||||
<refpurpose>define a new constraint trigger</refpurpose>
|
||||
</refnamediv>
|
||||
|
||||
<indexterm zone="sql-createconstraint">
|
||||
<primary>CREATE CONSTRAINT TRIGGER</primary>
|
||||
</indexterm>
|
||||
|
||||
<refsynopsisdiv>
|
||||
<synopsis>
|
||||
CREATE CONSTRAINT TRIGGER <replaceable class="parameter">name</replaceable>
|
||||
AFTER <replaceable class="parameter">event</replaceable> [ OR ... ]
|
||||
ON <replaceable class="parameter">table_name</replaceable>
|
||||
[ FROM <replaceable class="parameter">referenced_table_name</replaceable> ]
|
||||
{ NOT DEFERRABLE | [ DEFERRABLE ] { INITIALLY IMMEDIATE | INITIALLY DEFERRED } }
|
||||
FOR EACH ROW
|
||||
[ WHEN ( <replaceable class="parameter">condition</replaceable> ) ]
|
||||
EXECUTE PROCEDURE <replaceable class="parameter">function_name</replaceable> ( <replaceable class="parameter">arguments</replaceable> )
|
||||
</synopsis>
|
||||
</refsynopsisdiv>
|
||||
|
||||
<refsect1>
|
||||
<title>Description</title>
|
||||
|
||||
<para>
|
||||
<command>CREATE CONSTRAINT TRIGGER</command> creates a
|
||||
<firstterm>constraint trigger</>. This is the same as a regular trigger
|
||||
except that the timing of the trigger firing can be adjusted using
|
||||
<xref linkend="SQL-SET-CONSTRAINTS">.
|
||||
Constraint triggers must be <literal>AFTER ROW</> triggers. They can
|
||||
be fired either at the end of the statement causing the triggering event,
|
||||
or at the end of the containing transaction; in the latter case they are
|
||||
said to be <firstterm>deferred</>. A pending deferred-trigger firing can
|
||||
also be forced to happen immediately by using <command>SET CONSTRAINTS</>.
|
||||
</para>
|
||||
</refsect1>
|
||||
|
||||
<refsect1>
|
||||
<title>Parameters</title>
|
||||
|
||||
<variablelist>
|
||||
<varlistentry>
|
||||
<term><replaceable class="PARAMETER">name</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
The name of the constraint trigger. This is also the name to use
|
||||
when modifying the trigger's behavior using <command>SET CONSTRAINTS</>.
|
||||
The name cannot be schema-qualified — the trigger inherits the
|
||||
schema of its table.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><replaceable class="PARAMETER">event</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
One of <literal>INSERT</literal>, <literal>UPDATE</literal>, or
|
||||
<literal>DELETE</literal>; this specifies the event that will fire the
|
||||
trigger. Multiple events can be specified using <literal>OR</literal>.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><replaceable class="PARAMETER">table_name</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
The (possibly schema-qualified) name of the table in which
|
||||
the triggering events occur.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><replaceable class="PARAMETER">referenced_table_name</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
The (possibly schema-qualified) name of another table referenced by the
|
||||
constraint. This option is used for foreign-key constraints and is not
|
||||
recommended for general use.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><literal>DEFERRABLE</literal></term>
|
||||
<term><literal>NOT DEFERRABLE</literal></term>
|
||||
<term><literal>INITIALLY IMMEDIATE</literal></term>
|
||||
<term><literal>INITIALLY DEFERRED</literal></term>
|
||||
<listitem>
|
||||
<para>
|
||||
The default timing of the trigger.
|
||||
See the <xref linkend="SQL-CREATETABLE">
|
||||
documentation for details of these constraint options.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><replaceable class="parameter">condition</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
A Boolean expression that determines whether the trigger function
|
||||
will actually be executed. This acts the same as in <xref
|
||||
linkend="SQL-CREATETRIGGER">.
|
||||
Note in particular that evaluation of the <literal>WHEN</>
|
||||
condition is not deferred, but occurs immediately after the row
|
||||
update operation is performed. If the condition does not evaluate
|
||||
to <literal>true</> then the trigger is not queued for deferred
|
||||
execution.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><replaceable class="PARAMETER">function_name</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
The function to call when the trigger is fired. See <xref
|
||||
linkend="SQL-CREATETRIGGER"> for
|
||||
details.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><replaceable class="PARAMETER">arguments</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
Optional argument strings to pass to the trigger function. See <xref
|
||||
linkend="SQL-CREATETRIGGER"> for
|
||||
details.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
</variablelist>
|
||||
</refsect1>
|
||||
|
||||
<refsect1>
|
||||
<title>Compatibility</title>
|
||||
<para>
|
||||
<command>CREATE CONSTRAINT TRIGGER</command> is a
|
||||
<productname>PostgreSQL</productname> extension of the <acronym>SQL</>
|
||||
standard.
|
||||
</para>
|
||||
</refsect1>
|
||||
|
||||
<refsect1>
|
||||
<title>See Also</title>
|
||||
|
||||
<simplelist type="inline">
|
||||
<member><xref linkend="sql-createtrigger"></member>
|
||||
<member><xref linkend="sql-droptrigger"></member>
|
||||
<member><xref linkend="sql-set-constraints"></member>
|
||||
</simplelist>
|
||||
</refsect1>
|
||||
</refentry>
|
||||
@ -21,8 +21,10 @@ PostgreSQL documentation
|
||||
|
||||
<refsynopsisdiv>
|
||||
<synopsis>
|
||||
CREATE TRIGGER <replaceable class="PARAMETER">name</replaceable> { BEFORE | AFTER | INSTEAD OF } { <replaceable class="PARAMETER">event</replaceable> [ OR ... ] }
|
||||
CREATE [ CONSTRAINT ] TRIGGER <replaceable class="PARAMETER">name</replaceable> { BEFORE | AFTER | INSTEAD OF } { <replaceable class="PARAMETER">event</replaceable> [ OR ... ] }
|
||||
ON <replaceable class="PARAMETER">table</replaceable> [ FOR [ EACH ] { ROW | STATEMENT } ]
|
||||
[ FROM <replaceable class="parameter">referenced_table_name</replaceable> ]
|
||||
{ NOT DEFERRABLE | [ DEFERRABLE ] { INITIALLY IMMEDIATE | INITIALLY DEFERRED } }
|
||||
[ WHEN ( <replaceable class="parameter">condition</replaceable> ) ]
|
||||
EXECUTE PROCEDURE <replaceable class="PARAMETER">function_name</replaceable> ( <replaceable class="PARAMETER">arguments</replaceable> )
|
||||
</synopsis>
|
||||
@ -149,6 +151,20 @@ CREATE TRIGGER <replaceable class="PARAMETER">name</replaceable> { BEFORE | AFTE
|
||||
they will be fired in alphabetical order by name.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
When the <literal>CONSTRAINT</> option is specified, this command creates a
|
||||
<firstterm>constraint trigger</>. This is the same as a regular trigger
|
||||
except that the timing of the trigger firing can be adjusted using
|
||||
<xref linkend="SQL-SET-CONSTRAINTS">.
|
||||
Constraint triggers must be <literal>AFTER ROW</> triggers. They can
|
||||
be fired either at the end of the statement causing the triggering event,
|
||||
or at the end of the containing transaction; in the latter case they are
|
||||
said to be <firstterm>deferred</>. A pending deferred-trigger firing can
|
||||
also be forced to happen immediately by using <command>SET CONSTRAINTS</>.
|
||||
Constraint triggers are expected to raise an exception when the constraints
|
||||
they implement are violated.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
<command>SELECT</command> does not modify any rows so you cannot
|
||||
create <command>SELECT</command> triggers. Rules and views are more
|
||||
@ -170,6 +186,10 @@ CREATE TRIGGER <replaceable class="PARAMETER">name</replaceable> { BEFORE | AFTE
|
||||
<para>
|
||||
The name to give the new trigger. This must be distinct from
|
||||
the name of any other trigger for the same table.
|
||||
The name cannot be schema-qualified — the trigger inherits the
|
||||
schema of its table. For a constraint trigger, this is also the name to
|
||||
use when modifying the trigger's behavior using
|
||||
<command>SET CONSTRAINTS</>.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
@ -181,7 +201,8 @@ CREATE TRIGGER <replaceable class="PARAMETER">name</replaceable> { BEFORE | AFTE
|
||||
<listitem>
|
||||
<para>
|
||||
Determines whether the function is called before, after, or instead of
|
||||
the event.
|
||||
the event. A constraint trigger can only be specified as
|
||||
<literal>AFTER</>.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
@ -222,6 +243,33 @@ UPDATE OF <replaceable>column_name1</replaceable> [, <replaceable>column_name2</
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><replaceable class="PARAMETER">referenced_table_name</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
The (possibly schema-qualified) name of another table referenced by the
|
||||
constraint. This option is used for foreign-key constraints and is not
|
||||
recommended for general use. This can only be specified for
|
||||
constraint triggers.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><literal>DEFERRABLE</literal></term>
|
||||
<term><literal>NOT DEFERRABLE</literal></term>
|
||||
<term><literal>INITIALLY IMMEDIATE</literal></term>
|
||||
<term><literal>INITIALLY DEFERRED</literal></term>
|
||||
<listitem>
|
||||
<para>
|
||||
The default timing of the trigger.
|
||||
See the <xref linkend="SQL-CREATETABLE"> documentation for details of
|
||||
these constraint options. This can only be specified for constraint
|
||||
triggers.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><literal>FOR EACH ROW</literal></term>
|
||||
<term><literal>FOR EACH STATEMENT</literal></term>
|
||||
@ -231,7 +279,8 @@ UPDATE OF <replaceable>column_name1</replaceable> [, <replaceable>column_name2</
|
||||
This specifies whether the trigger procedure should be fired
|
||||
once for every row affected by the trigger event, or just once
|
||||
per SQL statement. If neither is specified, <literal>FOR EACH
|
||||
STATEMENT</literal> is the default.
|
||||
STATEMENT</literal> is the default. Constraint triggers can only
|
||||
be specified <literal>FOR EACH ROW</>.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
@ -263,6 +312,13 @@ UPDATE OF <replaceable>column_name1</replaceable> [, <replaceable>column_name2</
|
||||
Currently, <literal>WHEN</literal> expressions cannot contain
|
||||
subqueries.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
Note that for constraint triggers, evaluation of the <literal>WHEN</>
|
||||
condition is not deferred, but occurs immediately after the row update
|
||||
operation is performed. If the condition does not evaluate to true then
|
||||
the trigger is not queued for deferred execution.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
@ -481,6 +537,12 @@ CREATE TRIGGER view_insert
|
||||
ability to define statement-level triggers on views.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
<command>CREATE CONSTRAINT TRIGGER</command> is a
|
||||
<productname>PostgreSQL</productname> extension of the <acronym>SQL</>
|
||||
standard.
|
||||
</para>
|
||||
|
||||
</refsect1>
|
||||
|
||||
<refsect1>
|
||||
@ -490,6 +552,7 @@ CREATE TRIGGER view_insert
|
||||
<member><xref linkend="sql-createfunction"></member>
|
||||
<member><xref linkend="sql-altertrigger"></member>
|
||||
<member><xref linkend="sql-droptrigger"></member>
|
||||
<member><xref linkend="sql-set-constraints"></member>
|
||||
</simplelist>
|
||||
</refsect1>
|
||||
</refentry>
|
||||
|
||||
@ -74,7 +74,6 @@
|
||||
©Table;
|
||||
&createAggregate;
|
||||
&createCast;
|
||||
&createConstraint;
|
||||
&createConversion;
|
||||
&createDatabase;
|
||||
&createDomain;
|
||||
|
||||
Loading…
Reference in New Issue
Block a user