How do I delete a row using foreign key constraint in MySQL?

How do I delete a row using foreign key constraint in MySQL?

Simply execute as follows:

1. Disable foreign key check. SET foreign_key_checks = 0;
2. Delete your records. DELETE FROM table_name WHERE {conditions};
3. Enable foreign key check. SET foreign_key_checks = 1;

Can I delete a row with foreign key constraint?

You can alter a foreign key constraint with delete cascade option as shown below. This will delete chind table rows related to master table rows when deleted. If you have multiply rows to delete and you don’t want to alter the structure of your tables you can use cursor.

How do you delete a table that has a foreign key reference?

To delete a foreign key constraint

1. In Object Explorer, expand the table with the constraint and then expand Keys.
2. Right-click the constraint and then click Delete.
3. In the Delete Object dialog box, click OK.

How do I delete a specific row in MySQL?

To delete rows in a MySQL table, use the DELETE FROM statement: DELETE FROM products WHERE product_id=1; The WHERE clause is optional, but you’ll usually want it, unless you really want to delete every row from the table.

How do I delete a foreign key in MySQL?

Here’s the syntax for DROP FOREIGN KEY statement: ALTER TABLE table_name DROP FOREIGN KEY constraint_name; In the above drop foreign key query, specify table_name from which you want to remove foreign key, in place of table_name. Specify constraint name in place of constraint_name.

What is the meaning of On delete cascade?

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.

How do I delete a table in MySQL?

To delete a table, first login to MySQL: Enter your password and then switch to the database you want to edit by typing the following at the mysql> prompt: mysql> use [db name]; Finally, drop the table: mysql> drop table [table name]; Replace [table name] with the actual name of the table you want to remove. To remove a row, type:

How do I delete a record in MySQL?

If you want to delete a record from any MySQL table, then you can use the SQL command DELETE FROM. You can use this command at the mysql> prompt as well as in any script like PHP. The following code block has a generic SQL syntax of the DELETE command to delete data from a MySQL table.

How can we drop unique constraint from a mySQL table?

Drop Unique Constraint. The syntax for dropping a unique constraint in MySQL is: ALTER TABLE table_name DROP INDEX constraint_name; table_name The name of the table to modify. This is the table that you wish to remove the unique constraint from. constraint_name The name of the unique constraint to remove. Example

How do I disable foreign key in SQL?

Using Transact-SQL. To disable a foreign key constraint for INSERT and UPDATE statements. In Object Explorer, connect to an instance of Database Engine . On the Standard bar, click New Query. Copy and paste the following examples into the query window and click Execute.