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Editing and markup cleanup.

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This commit is contained in:
Thomas G. Lockhart
1998-09-22 15:48:03 +00:00
parent 748e300317
commit 52ca2ab268
23 changed files with 1222 additions and 926 deletions
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85
doc/src/sgml/ref/create_trigger.sgml
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@@ -14,30 +14,24 @@
</REFPURPOSE>
<REFSYNOPSISDIV>
<REFSYNOPSISDIVINFO>
<DATE>1998-04-15</DATE>
<DATE>1998-09-21</DATE>
</REFSYNOPSISDIVINFO>
<SYNOPSIS>
CREATE TRIGGER <REPLACEABLE CLASS="PARAMETER">name</REPLACEABLE> { BEFORE | AFTER }
{ <REPLACEABLE CLASS="PARAMETER">event</REPLACEABLE> [OR ...] }
ON <REPLACEABLE CLASS="PARAMETER">table</REPLACEABLE> FOR EACH { ROW | STATEMENT }
EXECUTE PROCEDURE <REPLACEABLE CLASS="PARAMETER">funcname</REPLACEABLE> ( <REPLACEABLE CLASS="PARAMETER">arguments</REPLACEABLE> )
CREATE TRIGGER <REPLACEABLE CLASS="PARAMETER">name</REPLACEABLE> { BEFORE | AFTER }
{ <REPLACEABLE CLASS="PARAMETER">event</REPLACEABLE> [OR ...] }
ON <REPLACEABLE CLASS="PARAMETER">table</REPLACEABLE> FOR EACH { ROW | STATEMENT }
EXECUTE PROCEDURE <REPLACEABLE CLASS="PARAMETER">funcname</REPLACEABLE> ( <REPLACEABLE CLASS="PARAMETER">arguments</REPLACEABLE> )
</SYNOPSIS>
<REFSECT2 ID="R2-SQL-CREATETRIGGER-1">
<REFSECT2INFO>
<DATE>1998-04-15</DATE>
<DATE>1998-09-21</DATE>
</REFSECT2INFO>
<TITLE>
Inputs
</TITLE>
<PARA>
</PARA>
<VARIABLELIST>
<VARLISTENTRY>
<TERM>
</TERM>
<LISTITEM>
<PARA>
<VARIABLELIST>
<VARLISTENTRY>
<TERM>
@@ -80,14 +74,11 @@
</LISTITEM>
</VARLISTENTRY>
</variablelist>
</LISTITEM>
</VARLISTENTRY>
</VARIABLELIST>
</REFSECT2>
<REFSECT2 ID="R2-SQL-CREATETRIGGER-2">
<REFSECT2INFO>
<DATE>1998-04-15</DATE>
<DATE>1998-09-21</DATE>
</REFSECT2INFO>
<TITLE>
Outputs
@@ -97,6 +88,7 @@
<VARIABLELIST>
<VARLISTENTRY>
<TERM>
<replaceable>status</replaceable>
</TERM>
<LISTITEM>
<PARA>
@@ -120,23 +112,17 @@
<REFSECT1 ID="R1-SQL-CREATETRIGGER-1">
<REFSECT1INFO>
<DATE>1998-04-15</DATE>
<DATE>1998-09-21</DATE>
</REFSECT1INFO>
<TITLE>
Description
</TITLE>
<PARA>
CREATE TRIGGER will enter a new trigger into the current
<command>CREATE TRIGGER</command> will enter a new trigger into the current
data base. The trigger will be associated with the relation
<replaceable class="parameter">relname</replaceable> and will execute
the specified function <replaceable class="parameter">funcname</replaceable>.
</PARA>
<PARA>
Only the relation owner may create a trigger on this relation.
</PARA>
<PARA>
At release 6.3.2, STATEMENT triggers are not implemented.
</PARA>
<PARA>
The trigger can be specified to fire either before the
operation is attempted on a tuple (before constraints
@@ -147,24 +133,32 @@
skip the operation for the current tuple, or change the tuple
being inserted (for INSERT and UPDATE operations only). If
the trigger fires after the event, all changes, including the
last INSERTion, UPDATE or DELETion, are "visible" to the trigger.
last insertion, update, or deletion, are "visible" to the trigger.
</PARA>
<PARA>
Refer to the SPI and trigger programming guides for more
Refer to the chapters on SPI and Triggers in the
<citetitle>PostgreSQL Programmer's Guide</citetitle> for more
information.
</PARA>
<REFSECT2 ID="R2-SQL-CREATETRIGGER-3">
<REFSECT2INFO>
<DATE>1998-04-15</DATE>
<DATE>1998-09-21</DATE>
</REFSECT2INFO>
<TITLE>
Notes
</TITLE>
<PARA>
CREATE TRIGGER statement is a PostgreSQL language extension.
<command>CREATE TRIGGER</command> is a <productname>Postgres</productname>
language extension.
</PARA>
<PARA>
Only the relation owner may create a trigger on this relation.
</PARA>
<PARA>
As of the current release (v6.4), STATEMENT triggers are not implemented.
</PARA>
<PARA>
Refer to the DROP TRIGGER statement for information on how to
Refer to <command>DROP TRIGGER</command> for information on how to
remove triggers.
</PARA>
@@ -179,18 +173,18 @@
table before appending or updating a row in the table films:
</PARA>
<ProgramListing>
CREATE TRIGGER if_dist_exists
BEFORE INSERT OR UPDATE ON films FOR EACH ROW
EXECUTE PROCEDURE check_primary_key ('did', 'distributors', 'did');
CREATE TRIGGER if_dist_exists
BEFORE INSERT OR UPDATE ON films FOR EACH ROW
EXECUTE PROCEDURE check_primary_key ('did', 'distributors', 'did');
</ProgramListing>
<PARA>
Before cancelling a distributor or updating its code, remove every
reference to the table films:
</PARA>
<ProgramListing>
CREATE TRIGGER if_film_exists
BEFORE DELETE OR UPDATE ON distributors FOR EACH ROW
EXECUTE PROCEDURE check_foreign_key (1, 'CASCADE', 'did', 'films', 'did');
CREATE TRIGGER if_film_exists
BEFORE DELETE OR UPDATE ON distributors FOR EACH ROW
EXECUTE PROCEDURE check_foreign_key (1, 'CASCADE', 'did', 'films', 'did');
</ProgramListing>
</REFSECT1>
@@ -203,29 +197,30 @@
<REFSECT2 ID="R2-SQL-CREATETRIGGER-4">
<REFSECT2INFO>
<DATE>1998-04-15</DATE>
<DATE>1998-09-21</DATE>
</REFSECT2INFO>
<TITLE>
SQL92
</TITLE>
<PARA>
There is no CREATE TRIGGER statement in SQL92.
There is no <command>CREATE TRIGGER</command> in <acronym>SQL92</acronym>.
</PARA>
<PARA>
The second example above may also be done by using a FOREIGN KEY
constraint as in:
</PARA>
<ProgramListing>
CREATE TABLE distributors (
did DECIMAL(3),
name VARCHAR(40),
CONSTRAINT if_film_exists FOREIGN KEY(did) REFERENCES films
ON UPDATE CASCADE ON DELETE CASCADE
);
CREATE TABLE distributors (
did DECIMAL(3),
name VARCHAR(40),
CONSTRAINT if_film_exists
FOREIGN KEY(did) REFERENCES films
ON UPDATE CASCADE ON DELETE CASCADE
);
</ProgramListing>
<PARA>
However, foreign keys are not yet implemented at version 6.3.2 of
PostgreSQL.
However, foreign keys are not yet implemented (as of version 6.4) in
<productname>Postgres</productname>.
</PARA>
</REFENTRY>