How to pass parameters to Oracle database trigger

Oracle database triggers can receive parameters to enhance flexibility. There are two ways to pass parameters: 1. Direct assignment: declare parameters in the trigger definition and use name access in the trigger code; 2. Use pragma autonomous_transaction: use pragma in the trigger definition and use autonomous_transaction in the trigger code. Function access parameters.

Oracle Database Trigger Parameter Passing

Triggers can receive parameters, which enhances their flexibility, Allows custom actions to be performed based on specific conditions. Oracle database supports passing parameters to triggers in two ways:

Method 1: Direct assignment

• Use colon (:) declaration in trigger definition Trigger parameters.
• In the trigger code, access the incoming parameter using its name.

Example:

<code class="sql">CREATE OR REPLACE TRIGGER my_trigger
BEFORE INSERT ON my_table
FOR EACH ROW
BEGIN
  :new.my_column := :old.my_column + 1;
END;</code>

Method 2: Use pragma autonomous_transaction

• in trigger definition Use pragma autonomous_transaction.
• In trigger code, use the autonomous_transaction function to access PL/SQL parameters.

Example:

<code class="sql">CREATE OR REPLACE TRIGGER my_trigger
PRAGMA AUTONOMOUS_TRANSACTION
BEFORE INSERT ON my_table
FOR EACH ROW
BEGIN
  autonomous_transaction.new.my_column := autonomous_transaction.old.my_column + 1;
END;</code>

Note:

• Trigger parameters can only be IN parameters .
• The passed parameter value remains unchanged during trigger execution.
• When using pragma autonomous_transaction, the trigger will run in the AUTONOMOUS transaction, isolated from the transaction called by the trigger.

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