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What does references Column_name on delete cascade mean?
DELETE CASCADE: When we create a foreign key using this option, it deletes the referencing rows in the child table when the referenced row is deleted in the parent table which has a primary key.
What does on update cascade mean in MySQL?
The ON UPDATE CASCADE tells the database that when an update occurs on the referenced column from the parent table (“ id ”), it must automatically update the matching rows in the child table (“ books ”) with the new value.
How to create foreign key with Cascade delete in SQL Server?
A foreign key with cascade delete means that if a record in the parent table is deleted, then the corresponding records in the child table will automatically be deleted. This is called a cascade delete in SQL Server. A foreign key with cascade delete can be created using either a CREATE TABLE statement or an ALTER TABLE statement.
When to use on delete Cascade clause in MySQL?
ON DELETE CASCADE clause in MySQL is used to automatically remove the matching records from the child table when we delete the rows from the parent table. It is a kind of referential action related to the foreign key. Suppose we have created two tables with a FOREIGN KEY in a foreign key relationship, making both tables a parent and child.
When to update cascade in a foreign key?
UPDATE CASCADE: When we create a foreign key using UPDATE CASCADE the referencing rows are updated in the child table when the referenced row is updated in the parent table which has a primary key. We will be discussing the following topics in this article: Creating DELETE and UPDATE CASCADE rule in a foreign key using SQL Server management studio
How to create foreign key with delete rule?
In the INSERT and UPDATE specifications, select Cascade for the delete rule. Click on Close and save the table in the designer. Click Yes in the warning message window. Once you click on Yes, a foreign key with delete rule is created.