Search results
This tutorial shows you how to use MySQL ON DELETE CASCADE to automatically delete data from a child table when you delete data from the parent table.
ON UPDATE CASCADE. )Engine=InnoDB; This way, you can delete a product OR a category, and only the associated records in categories_products will die alongside. The cascade won't travel farther up the tree and delete the parent product/category table. e.g. products: boots, mittens, hats, coats.
8 lut 2021 · ON DELETE CASCADE constraint is used in MySQL to delete the rows from the child table automatically, when the rows from the parent table are deleted. For example when a student registers in an online learning platform, then all the details of the student are recorded with their unique number/id.
The MySQL ON DELETE CASCADE constraint ensures that when a row in the parent table is deleted, all related rows in the child table are automatically deleted as well. This constraint helps maintain referential integrity between two tables that are connected through a foreign key relationship.
27 sty 2024 · Using cascade delete in MySQL is a powerful feature that can help maintain data integrity and remove orphans dynamically.
20 cze 2013 · ON DELETE CASCADE: if a row of the referenced table is deleted, then all matching rows in the referencing table are deleted. ON DELETE SET NULL : if a row of the referenced table is deleted, then all referencing columns in all matching rows of the referencing table to be set to null.
Podsumowanie: W tym poradniku dowiesz się, jak używać MySQL ON DELETE CASCADE akcji referencji dla klucza obcego do usuwania danych z wielu powiązanych tabel. W poprzednim poradniku dowiedziałeś się, jak usunąć dane z wielu powiązanych tabel za pomocą pojedynczej instrukcji DELETE.
