KEY_COLUMN_USAGE (Transact-SQL)

THIS TOPIC APPLIES TO:yesSQL Server (starting with 2008)noAzure SQL DatabasenoAzure SQL Data Warehouse noParallel Data Warehouse

Returns one row for each column that is constrained as a key in the current database. This information schema view returns information about the objects to which the current user has permissions.

To retrieve information from these views, specify the fully qualified name of INFORMATION_SCHEMA.view_name.

Column name Data type Description
CONSTRAINT_CATALOG nvarchar(128) Constraint qualifier.
CONSTRAINT_SCHEMA nvarchar(128) Name of schema that contains the constraint.

** Important *\* Do not use INFORMATION_SCHEMA views to determine the schema of an object. The only reliable way to find the schema of a object is to query the sys.objects catalog view.
CONSTRAINT_NAME nvarchar(128) Constraint name.
TABLE_CATALOG nvarchar(128) Table qualifier.
TABLE_SCHEMA nvarchar(128) Name of schema that contains the table.

** Important *\* Do not use INFORMATION_SCHEMA views to determine the schema of an object. The only reliable way to find the schema of a object is to query the sys.objects catalog view.
TABLE_NAME nvarchar(128) Table name.
COLUMN_NAME nvarchar(128) Column name.
ORDINAL_POSITION int Column ordinal position.

See Also

System Views (Transact-SQL)
Information Schema Views (Transact-SQL)
sys.columns (Transact-SQL)
sys.indexes (Transact-SQL)
sys.objects (Transact-SQL)
sys.foreign_keys (Transact-SQL)
sys.key_constraints (Transact-SQL)