<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >pg_trigger</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REV="MADE" HREF="mailto:pgsql-docs@postgresql.org"><LINK REL="HOME" TITLE="PostgreSQL 8.4.8 Documentation" HREF="index.html"><LINK REL="UP" TITLE="System Catalogs" HREF="catalogs.html"><LINK REL="PREVIOUS" TITLE="pg_tablespace" HREF="catalog-pg-tablespace.html"><LINK REL="NEXT" TITLE="pg_ts_config" HREF="catalog-pg-ts-config.html"><LINK REL="STYLESHEET" TYPE="text/css" HREF="stylesheet.css"><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"><META NAME="creation" CONTENT="2011-04-15T03:27:09"></HEAD ><BODY CLASS="SECT1" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" >PostgreSQL 8.4.8 Documentation</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="catalog-pg-tablespace.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="catalogs.html" >Fast Backward</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" >Chapter 44. System Catalogs</TD ><TD WIDTH="10%" ALIGN="right" VALIGN="top" ><A HREF="catalogs.html" >Fast Forward</A ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="top" ><A HREF="catalog-pg-ts-config.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="CATALOG-PG-TRIGGER" >44.36. <TT CLASS="STRUCTNAME" >pg_trigger</TT ></A ></H1 ><A NAME="AEN77427" ></A ><P > The catalog <TT CLASS="STRUCTNAME" >pg_trigger</TT > stores triggers on tables. See <A HREF="sql-createtrigger.html" ><I >CREATE TRIGGER</I ></A > for more information. </P ><DIV CLASS="TABLE" ><A NAME="AEN77432" ></A ><P ><B >Table 44-36. <TT CLASS="STRUCTNAME" >pg_trigger</TT > Columns</B ></P ><TABLE BORDER="1" CLASS="CALSTABLE" ><COL><COL><COL><COL><THEAD ><TR ><TH >Name</TH ><TH >Type</TH ><TH >References</TH ><TH >Description</TH ></TR ></THEAD ><TBODY ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgrelid</TT ></TD ><TD ><TT CLASS="TYPE" >oid</TT ></TD ><TD ><TT CLASS="LITERAL" ><A HREF="catalog-pg-class.html" ><TT CLASS="STRUCTNAME" >pg_class</TT ></A >.oid</TT ></TD ><TD >The table this trigger is on</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgname</TT ></TD ><TD ><TT CLASS="TYPE" >name</TT ></TD ><TD > </TD ><TD >Trigger name (must be unique among triggers of same table)</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgfoid</TT ></TD ><TD ><TT CLASS="TYPE" >oid</TT ></TD ><TD ><TT CLASS="LITERAL" ><A HREF="catalog-pg-proc.html" ><TT CLASS="STRUCTNAME" >pg_proc</TT ></A >.oid</TT ></TD ><TD >The function to be called</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgtype</TT ></TD ><TD ><TT CLASS="TYPE" >int2</TT ></TD ><TD > </TD ><TD >Bit mask identifying trigger conditions</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgenabled</TT ></TD ><TD ><TT CLASS="TYPE" >char</TT ></TD ><TD > </TD ><TD > Controls in which <A HREF="runtime-config-client.html#GUC-SESSION-REPLICATION-ROLE" >session_replication_role</A > modes the trigger fires. <TT CLASS="LITERAL" >O</TT > = trigger fires in <SPAN CLASS="QUOTE" >"origin"</SPAN > and <SPAN CLASS="QUOTE" >"local"</SPAN > modes, <TT CLASS="LITERAL" >D</TT > = trigger is disabled, <TT CLASS="LITERAL" >R</TT > = trigger fires in <SPAN CLASS="QUOTE" >"replica"</SPAN > mode, <TT CLASS="LITERAL" >A</TT > = trigger fires always. </TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgisconstraint</TT ></TD ><TD ><TT CLASS="TYPE" >bool</TT ></TD ><TD > </TD ><TD >True if trigger is a <SPAN CLASS="QUOTE" >"constraint trigger"</SPAN ></TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgconstrname</TT ></TD ><TD ><TT CLASS="TYPE" >name</TT ></TD ><TD > </TD ><TD >Constraint name, if a constraint trigger</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgconstrrelid</TT ></TD ><TD ><TT CLASS="TYPE" >oid</TT ></TD ><TD ><TT CLASS="LITERAL" ><A HREF="catalog-pg-class.html" ><TT CLASS="STRUCTNAME" >pg_class</TT ></A >.oid</TT ></TD ><TD >The table referenced by a referential integrity constraint</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgconstraint</TT ></TD ><TD ><TT CLASS="TYPE" >oid</TT ></TD ><TD ><TT CLASS="LITERAL" ><A HREF="catalog-pg-constraint.html" ><TT CLASS="STRUCTNAME" >pg_constraint</TT ></A >.oid</TT ></TD ><TD >The <TT CLASS="STRUCTNAME" >pg_constraint</TT > entry owning the trigger, if any</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgdeferrable</TT ></TD ><TD ><TT CLASS="TYPE" >bool</TT ></TD ><TD > </TD ><TD >True if constraint trigger is deferrable</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tginitdeferred</TT ></TD ><TD ><TT CLASS="TYPE" >bool</TT ></TD ><TD > </TD ><TD >True if constraint trigger is initially deferred</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgnargs</TT ></TD ><TD ><TT CLASS="TYPE" >int2</TT ></TD ><TD > </TD ><TD >Number of argument strings passed to trigger function</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgattr</TT ></TD ><TD ><TT CLASS="TYPE" >int2vector</TT ></TD ><TD > </TD ><TD >Currently unused</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >tgargs</TT ></TD ><TD ><TT CLASS="TYPE" >bytea</TT ></TD ><TD > </TD ><TD >Argument strings to pass to trigger, each NULL-terminated</TD ></TR ></TBODY ></TABLE ></DIV ><DIV CLASS="NOTE" ><BLOCKQUOTE CLASS="NOTE" ><P ><B >Note: </B > When <TT CLASS="STRUCTFIELD" >tgconstraint</TT > is nonzero, <TT CLASS="STRUCTFIELD" >tgisconstraint</TT > must be true, and <TT CLASS="STRUCTFIELD" >tgconstrname</TT >, <TT CLASS="STRUCTFIELD" >tgconstrrelid</TT >, <TT CLASS="STRUCTFIELD" >tgdeferrable</TT >, <TT CLASS="STRUCTFIELD" >tginitdeferred</TT > are redundant with the referenced <TT CLASS="STRUCTNAME" >pg_constraint</TT > entry. The reason we keep these fields is that we support <SPAN CLASS="QUOTE" >"stand-alone"</SPAN > constraint triggers with no corresponding <TT CLASS="STRUCTNAME" >pg_constraint</TT > entry. </P ></BLOCKQUOTE ></DIV ><DIV CLASS="NOTE" ><BLOCKQUOTE CLASS="NOTE" ><P ><B >Note: </B > <TT CLASS="LITERAL" >pg_class.relhastriggers</TT > must be true if a table has any triggers in this catalog. </P ></BLOCKQUOTE ></DIV ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="catalog-pg-tablespace.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="catalog-pg-ts-config.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><TT CLASS="STRUCTNAME" >pg_tablespace</TT ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="catalogs.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><TT CLASS="STRUCTNAME" >pg_ts_config</TT ></TD ></TR ></TABLE ></DIV ></BODY ></HTML >