sys-key-constraints-transact-sql.md

title	sys.key_constraints (Transact-SQL) | Microsoft Docs
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ms.date	03/15/2017
ms.prod	sql
ms.prod_service	database-engine, sql-database, sql-data-warehouse, pdw
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ms.technology	system-objects
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f1_keywords	sys.key_constraints key_constraints sys.key_constraints_TSQL key_constraints_TSQL
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helpviewer_keywords	sys.key_constraints catalog view
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author	stevestein
ms.author	sstein
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sys.key_constraints (Transact-SQL)

[!INCLUDEtsql-appliesto-ss2008-all-md]

Contains a row for each object that is a primary key or unique constraint. Includes sys.objects.type PK and UQ.

Column name	Data type	Description
<Columns inherited from sys.objects>		For a list of columns that this view inherits, see sys.objects (Transact-SQL).
unique_index_id	int	ID of the corresponding unique index in the parent object that was created to enforce this constraint.
is_system_named	bit	1 = Name was generated by system. 0 = Name was supplied by the user.

Permissions

[!INCLUDEssCatViewPerm] For more information, see Metadata Visibility Configuration.

See Also

Object Catalog Views (Transact-SQL)
Catalog Views (Transact-SQL)
Querying the SQL Server System Catalog FAQ