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sp_pkeys (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) Warehouse in Microsoft Fabric

Returns primary key information for a single table in the current environment.

Transact-SQL syntax conventions

Syntax

Syntax for SQL Server, Azure SQL Database, Azure Synapse Analytics, Analytics Platform System (PDW).

sp_pkeys
    [ @table_name = ] N'table_name'
    [ , [ @table_owner = ] N'table_owner' ]
    [ , [ @table_qualifier = ] N'table_qualifier' ]
[ ; ]

Arguments

[ @table_name = ] N'table_name'

Specifies the table for which to return information. @table_name is sysname, with no default. Wildcard pattern matching isn't supported.

[ @table_owner = ] N'table_owner'

Specifies the table owner of the specified table. @table_owner is sysname, with a default of NULL. Wildcard pattern matching isn't supported. If @table_owner isn't specified, the default table visibility rules of the underlying database management system (DBMS) apply.

In SQL Server, if the current user owns a table with the specified name, the columns of that table are returned. If the @table_owner isn't specified, and the current user doesn't own a table with the specified @table_name, this procedure looks for a table with the specified @table_name owned by the database owner. If one exists, the columns of that table are returned.

[ @table_qualifier = ] N'table_qualifier'

The table qualifier. @table_qualifier is sysname, with a default of NULL. Various DBMS products support three-part naming for tables (<qualifier>.<owner>.<name>). In SQL Server, this column represents the database name. In some products, it represents the server name of the database environment of the table.

Return code values

None.

Result set

Column name Data type Description
TABLE_QUALIFIER sysname Name of the table qualifier. This field can be NULL.
TABLE_OWNER sysname Name of the table owner. This field always returns a value.
TABLE_NAME sysname Name of the table. In SQL Server, this column represents the table name as listed in the sysobjects table. This field always returns a value.
COLUMN_NAME sysname Name of the column, for each column of the TABLE_NAME returned. In SQL Server, this column represents the column name as listed in the sys.columns table. This field always returns a value.
KEY_SEQ smallint Sequence number of the column in a multicolumn primary key.
PK_NAME sysname Primary key identifier. Returns NULL if not applicable to the data source.

Remarks

sp_pkeys returns information about columns explicitly defined with a PRIMARY KEY constraint. Because not all systems support explicitly named primary keys, the gateway implementer determines what constitutes a primary key. The term primary key refers to a logical primary key for a table. Every key listed as being a logical primary key is expected to have a unique index defined on it. This unique index is also returned in sp_statistics.

The sp_pkeys stored procedure is equivalent to SQLPrimaryKeys in ODBC. Results are ordered by TABLE_QUALIFIER, TABLE_OWNER, TABLE_NAME, and KEY_SEQ.

Permissions

Requires SELECT permission on the schema.

Examples

The Transact-SQL code samples in this article use the AdventureWorks2022 or AdventureWorksDW2022 sample database, which you can download from the Microsoft SQL Server Samples and Community Projects home page.

The following example retrieves the primary key for the HumanResources.Department table in the AdventureWorks2022 database.

USE AdventureWorks2022;
GO

EXEC sp_pkeys @table_name = N'Department',
    @table_owner = N'HumanResources';

Examples: Azure Synapse Analytics and Analytics Platform System (PDW)

The following example retrieves the primary key for the DimAccount table in the AdventureWorksPDW2012 database. It returns zero rows indicating that the table doesn't have a primary key.

-- Uses AdventureWorksPDW

EXEC sp_pkeys @table_name = N'DimAccount';