<refsynopsisdiv>
<synopsis>
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 } ]
+ ON <replaceable class="PARAMETER">table</replaceable>
[ FROM <replaceable class="parameter">referenced_table_name</replaceable> ]
{ NOT DEFERRABLE | [ DEFERRABLE ] { INITIALLY IMMEDIATE | INITIALLY DEFERRED } }
+ [ FOR [ EACH ] { ROW | STATEMENT } ]
[ WHEN ( <replaceable class="parameter">condition</replaceable> ) ]
EXECUTE PROCEDURE <replaceable class="PARAMETER">function_name</replaceable> ( <replaceable class="PARAMETER">arguments</replaceable> )
</synopsis>
deletes fire <emphasis>after</> the cascaded <literal>DELETE</> completes.
The <productname>PostgreSQL</productname> behavior is for <literal>BEFORE
DELETE</literal> to always fire before the delete action, even a cascading
- one. This is considered more consistent. There is also unpredictable
- behavior when <literal>BEFORE</literal> triggers modify rows or prevent
+ one. This is considered more consistent. There is also nonstandard
+ behavior if <literal>BEFORE</literal> triggers modify rows or prevent
updates during an update that is caused by a referential action. This can
lead to constraint violations or stored data that does not honor the
referential constraint.