How do you call a trigger in PL SQL?

How do you call a trigger in SQL?


  1. Write a basic CREATE TRIGGER statement specifying the desired trigger attributes. …
  2. In the trigger action portion of the trigger you can declare SQL variables for any IN, INOUT, OUT parameters that the procedure specifies. …
  3. In the trigger action portion of the trigger add a CALL statement for the procedure.

How do I run a trigger in Oracle?

How to create a trigger in Oracle

  1. 1) CREATE OR REPLACE. The CREATE keyword specifies that you are creating a new trigger. …
  2. 2) Trigger name. …
  3. 3) BEFORE | AFTER. …
  4. 4) ON table_name. …
  5. 5) FOR EACH ROW. …
  6. 6) ENABLE / DISABLE. …
  7. 7) FOLLOWS | PRECEDES another_trigger.

What is trigger in PL SQL?

A PL/SQL trigger is a named database object that encapsulates and defines a set of actions that are to be performed in response to an insert, update, or delete operation against a table. Triggers are created using the PL/SQL CREATE TRIGGER statement.

Are triggers part of PL SQL?

Triggers in oracle are blocks of PL/SQL code which oracle engine can execute automatically based on some action or event. These events can be: DDL statements (CREATE, ALTER, DROP, TRUNCATE)

IT IS INTERESTING:  What must be installed to run PHP script?

Can trigger call stored procedure?

A: Yes, we can call stored procedure inside the trigger. For example: Create PROCEDURE [dbo].

How do you create a trigger?

create trigger [trigger_name]: Creates or replaces an existing trigger with the trigger_name. [before | after]: This specifies when the trigger will be executed. {insert | update | delete}: This specifies the DML operation. on [table_name]: This specifies the name of the table associated with the trigger.

How do you check if a trigger is fired?

To test if a trigger fires you can add a PRINT statement to the trigger (e.g. “PRINT ‘trigger fired!’ “), then do something that should trigger the trigger. If you get the printed text in your messages-tab in management studio you know it fired.

Can we commit inside a trigger?

Any change that a trigger does is committed with the transaction that fired the trigger. So yes, the change done inside the trigger will be committed “automatically”. You can’t commit inside a trigger anyway.

How many types of triggers exist in PL SQL?

Answer: There are two types of triggers in PL/SQL. They are Row-level trigger and Statement-level trigger.

What is trigger in PL SQL with examples?

Triggers are stored programs, which are automatically executed or fired when some events occur. Triggers are, in fact, written to be executed in response to any of the following events − A database manipulation (DML) statement (DELETE, INSERT, or UPDATE) A database definition (DDL) statement (CREATE, ALTER, or DROP).

What is the purpose of trigger?

Triggers are used to maintain the referential integrity of data by changing the data in a systematic fashion. Each trigger is attached to a single, specified table in the database. Triggers can be viewed as similar to stored procedures in that both consist of procedural logic that is stored at the database level.

IT IS INTERESTING:  Question: How do I start SQL Server automatically?