Delete foreign key relationships

Applies to: SQL Server 2016 (13.x) and later Azure SQL Database Azure SQL Managed Instance

You can delete a foreign key constraint in SQL Server by using SQL Server Management Studio or Transact-SQL. Deleting a foreign key constraint removes the requirement to enforce referential integrity.

Foreign keys reference keys in other tables, for more information, see Primary and Foreign Key Constraints.

Permissions

Requires ALTER permission on the table.

Use SQL Server Management Studio

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 select Delete.

3. In the Delete Object dialog box, select OK.

Use Transact-SQL

To delete a foreign key constraint

1. In Object Explorer, connect to an instance of Database Engine.

2. On the Standard bar, select New Query.

3. Copy and paste the following example into the query window and select Execute.

   USE AdventureWorks2022;
   GO
   ALTER TABLE dbo.DocExe
   DROP CONSTRAINT FK_Column_B;
   GO
   

For more information, see ALTER TABLE (Transact-SQL).

Next steps

• ALTER TABLE (Transact-SQL)
• sys.key_constraints (Transact-SQL)
• Create Foreign Key Relationships
• Modify Foreign Key Relationships