on delete cascade
时间: 2024-01-28 20:05:18 浏览: 25
ON DELETE CASCADE is a referential action that can be applied to a foreign key constraint in a database. When a foreign key constraint has ON DELETE CASCADE, it means that if a record is deleted from the parent table, all related records in the child table will also be deleted automatically.
For example, if there are two tables, Orders and OrderDetails, and OrderDetails has a foreign key constraint referencing Orders, with ON DELETE CASCADE. If a record is deleted from the Orders table, all related records in the OrderDetails table will also be deleted automatically.
This feature can be useful in cases where you want to ensure that data consistency is maintained between the parent and child tables. However, it is important to use it with caution, as it can result in unintended data loss if not properly managed.