- What is Cascade
- Cascade automatically propagates changes between related tables in SQL Server
- It maintains data integrity by automatically updating or deleting related records
- DELETE CASCADE
- Deletes child rows when parent row is deleted
- Prevents orphan rows in child tables
- Works with multiple foreign keys in a table
- Benefits
- Ensures data consistency and up-to-date relationships
- Saves time and effort in manual record management
- Reduces errors in related record operations
- Implementation
- Requires removing foreign key constraint from child table first
- Can be defined using ON DELETE or ON UPDATE CASCADE clauses
- Default action is ON DELETE NO ACTION
- Error Handling
- Non-existent parent references result in constraint violation errors
- Cascade rules can be applied to multiple foreign keys