Asked by: Vivian Soussi
technology and computing databases

How do I delete a foreign key constraint in SQL Server?

Last Updated: 1st July, 2020

14
To delete a foreign key constraint
  1. In Object Explorer, expand the table with the constraintand then expand Keys.
  2. Right-click the constraint and then clickDelete.
  3. In the Delete Object dialog box, click OK.

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Keeping this in view, can we delete a foreign key?

A foreign key with cascade delete meansthat if a record in the parent table is deleted, thenthe corresponding records in the child tablewill automatically be deleted. A foreign keywith cascade delete can be created using either a CREATETABLE statement or an ALTER TABLE statement.

Beside above, what is foreign key constraint in SQL Server? SQL FOREIGN KEY Constraint. A FOREIGN KEYis a key used to link two tables together. A FOREIGNKEY is a field (or collection of fields) in one table thatrefers to the PRIMARY KEY in another table. The FOREIGNKEY constraint is used to prevent actions that would destroylinks between tables.

how do I delete a constraint in SQL Server?

Using SQL Server Management Studio

  1. In Object Explorer, expand the table with the checkconstraint.
  2. Expand Constraints.
  3. Right-click the constraint and click Delete.
  4. In the Delete Object dialog box, click OK.

How do I cascade delete in SQL Server?

To add "Cascade delete" to an existing foreignkey in SQL Server Management Studio: First, select yourForeign Key, and open it's "DROP and Create To.." in a new Querywindow. Then, just add ON DELETE CASCADE to the ADDCONSTRAINT command: And hit the "Execute" button to run thisquery.

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