Three triggering methods of sql trigger

SQL trigger triggering methods are: BEFORE: Triggered before data modification, used to enforce business rules. AFTER INSERT: Triggered after inserting a new row, used to add or update data to other tables. AFTER UPDATE: Triggered after updating an existing row, used to update related tables or record change history.

Three triggering methods of SQL trigger

SQL trigger is a database object that is used to Automatically perform specified actions when changes are made to data in a specific table. Triggers have three firing methods that define when to fire:

1. BEFORE

BEFORE triggers fire before changes are made to the table. It allows operations to be performed before data changes are written to the database. This is often used to enforce business rules, such as ensuring data conforms to a specific format or restriction.

2. AFTER INSERT

The AFTER INSERT trigger fires after a new row is inserted into the table. It allows operations to be performed after the data has been inserted into the database. This is typically used to create or update records in other tables, or to send notifications or emails.

3. AFTER UPDATE

AFTER UPDATE trigger fires after updating an existing row in the table. It allows operations to be performed after the data has been updated. This is typically used to update records in related tables, or to record a history of data changes.

Choose a trigger method

Choosing the appropriate trigger method depends on the operation to be performed and at which stage of the data change cycle the trigger should occur. Here are some guidelines:

• BEFORE Triggers are used to enforce business rules and data integrity.
• AFTER INSERT Triggers are used to add or update data to other tables.
• AFTER UPDATE Triggers are used to update related tables or record change history.

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