sys.key_constraints (Transact-SQL)
Applies to: 
SQL Server
Azure SQL Database
Azure SQL Managed Instance
Azure Synapse Analytics
Analytics Platform System (PDW)
Warehouse in Microsoft Fabric
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
The visibility of the metadata in catalog views is limited to securables that a user either owns, or on which the user was granted some permission. 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