Package org.postgresql.pljava.example.annotation

Class Triggers

java.lang.Object

org.postgresql.pljava.example.annotation.Triggers

@SQLAction(provides="foobar tables",install={"CREATE TABLE javatest.foobar_1 ( username text, stuff text )","CREATE TABLE javatest.foobar_2 ( username text, value numeric )"},remove={"DROP TABLE javatest.foobar_2","DROP TABLE javatest.foobar_1"}) @SQLAction(requires="constraint triggers",install="INSERT INTO javatest.foobar_2(value) VALUES (45)") @SQLAction(requires="foobar triggers",provides="foobar2_42",install="INSERT INTO javatest.foobar_2(value) VALUES (42)") @SQLAction(requires={"transition triggers","foobar2_42"},install="UPDATE javatest.foobar_2 SET value = 43 WHERE value = 42")
public class Triggers
extends Object

Example creating a couple of tables, and a function to be called when triggered by insertion into either table. In PostgreSQL 10 or later, also create a function and trigger that uses transition tables.

This example relies on implementor tags reflecting the PostgreSQL version, set up in the ConditionalDDR example. Transition tables appear in PG 10.

Constructor Summary

Constructors

Constructor	Description
Triggers()

Method Summary

Modifier and Type	Method	Description
static void	disallow44(TriggerData td)	Throw exception if value to be inserted is 44.
static void	examineRows(TriggerData td)	Examine old and new rows in reponse to a trigger.
static void	insertUsername(TriggerData td)	insert user name in response to a trigger.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Triggers

public Triggers()

Method Details

insertUsername

@Function(requires="foobar tables",provides="foobar triggers",schema="javatest",security=INVOKER,triggers={@Trigger(called=BEFORE,table="foobar_1",events=INSERT),@Trigger(called=BEFORE,scope=ROW,table="foobar_2",events=INSERT)})
public static void insertUsername(TriggerData td)
                           throws SQLException

insert user name in response to a trigger.

Throws:

SQLException

examineRows

@Function(implementor="postgresql_ge_100000",
          requires="foobar tables",
          provides="transition triggers",
          schema="javatest",
          security=INVOKER,
          triggers=@Trigger(called=AFTER,table="foobar_2",events=UPDATE,tableOld="oldrows",tableNew="newrows"))
public static void examineRows(TriggerData td)
                        throws SQLException

Examine old and new rows in reponse to a trigger. Transition tables first became available in PostgreSQL 10.

Throws:

SQLException

disallow44

@Function(requires="foobar tables",
          provides="constraint triggers",
          schema="javatest",
          security=INVOKER,
          triggers=@Trigger(called=AFTER,table="foobar_2",events=INSERT,scope=ROW,constraint=NOT_DEFERRABLE))
public static void disallow44(TriggerData td)
                       throws SQLException

Throw exception if value to be inserted is 44.

Throws:

SQLException