How do I delete a foreign key in MySQL?

How do I delete a foreign key?

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 MySQL FK?

You can drop a foreign key constraint using the following ALTER TABLE syntax: ALTER TABLE tbl_name DROP FOREIGN KEY fk_symbol; If the FOREIGN KEY clause defined a CONSTRAINT name when you created the constraint, you can refer to that name to drop the foreign key constraint.

How do I remove a foreign key constraint in mysql workbench?

To drop a foreign key, right-click the row you wish to delete, then select the Delete Selected FKs menu item. To modify properties of a foreign key, select it and make the desired changes.

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 we delete a row with foreign key?

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.

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What is Cascade delete in MySQL?

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 change my foreign key?

To modify a foreign key

  1. In Object Explorer, expand the table with the foreign key and then expand Keys.
  2. Right-click the foreign key to be modified and select Modify.
  3. In the Foreign Key Relationships dialog box, you can make the following modifications. Selected Relationship. …
  4. On the File menu, click Savetable name.

How can delete foreign key constraint in SQL Server using query?

You can try it if the commands do not work.

  1. Expand your database view.
  2. Right Click on Table which has foreign key constraint. …
  3. Right click on the column which has the foreign key reference. …
  4. A list of relationships will appear (if you have one) in a pop up window.
  5. From there you can delete the foreign key constraint.

What happens when we delete foreign key?

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. … A foreign key with cascade delete can be created using either a CREATE TABLE statement or an ALTER TABLE statement.

Can we delete constraints in primary or foreign key?

To successfully change or delete a row in a foreign key constraint, you must first either delete the foreign key data in the foreign key table or change the foreign key data in the foreign key table, which links the foreign key to different primary key data.

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