OBJECT_ID (Transact-SQL)

Artikel
12/03/2008

Returns the database object identification number of a schema-scoped object.

Topic link icon Transact-SQL Syntax Conventions

Important

Objects that are not schema-scoped, such as DDL triggers, cannot be queried by using OBJECT_ID. For objects that are not found in the sys.objects catalog view, obtain the object identification numbers by querying the appropriate catalog view. For example, to return the object identification number of a DDL trigger, use SELECT OBJECT_ID FROM sys.triggers WHERE name = 'DatabaseTriggerLog'

Syntax

OBJECT_ID ( '[ database_name . [ schema_name ] . | schema_name . ] 
    object_name' [ ,'object_type' ] )

Arguments

'object_name'
Is the object to be used. object_name is either varchar or nvarchar. If object_name is varchar, it is implicitly converted to nvarchar. Specifying the database and schema names is optional.

'object_type'
Is the schema-scoped object type. object_type is either varchar or nvarchar. If object_type is varchar, it is implicitly converted to nvarchar. For a list of object types, see the type column in sys.objects (Transact-SQL).

Return Types

int

Exceptions

Returns NULL on error.

In SQL Server 2005, a user can only view the metadata of securables that the user owns or on which the user has been granted permission. This means that metadata-emitting, built-in functions such as OBJECT_ID may return NULL if the user does not have any permission on the object. For more information, see Metadata Visibility Configuration and Troubleshooting Metadata Visibility.

Remarks

When the parameter to a system function is optional, the current database, host computer, server user, or database user is assumed. Built-in functions must always be followed by parentheses.

When a temporary table name is specified, the database name must come before the temporary table name, unless the current database is tempdb. For example: SELECT OBJECT_ID('tempdb..#mytemptable').

System functions can be used in the select list, in the WHERE clause, and anywhere an expression is allowed. For more information, see Expressions (Transact-SQL) and WHERE (Transact-SQL).

Examples

A. Returning the object ID for a specified object

The following example returns the object ID for the Production.WorkOrder table in the AdventureWorks database.

USE master;
GO
SELECT OBJECT_ID(N'AdventureWorks.Production.WorkOrder') AS 'Object ID';
GO

B. Verifying that an object exists

The following example checks for the existence of a specified table by verifying that the table has an object ID. If the table exists, it is deleted. If the table does not exist, the DROP TABLE statement is not executed.

USE AdventureWorks;
GO
IF OBJECT_ID (N'dbo.AWBuildVersion', N'U') IS NOT NULL
DROP TABLE dbo.AWBuildVersion;
GO

C. Using OBJECT_ID to specify the value of a system function parameter

The following example returns information for all indexes and partitions of the Person.Address table in the AdventureWorks database by using the sys.dm_db_index_operational_stats function.

Important

When you are using the Transact-SQL functions DB_ID and OBJECT_ID to return a parameter value, always make sure that a valid ID is returned. If the database or object name cannot be found, such as when they do not exist or are spelled incorrectly, both functions will return NULL. The sys.dm_db_index_operational_stats function interprets NULL as a wildcard value that specifies all databases or all objects. Because this can be an unintentional operation, the examples in this section demonstrate the safe way to determine database and object IDs.

DECLARE @db_id smallint;
DECLARE @object_id int;
SET @db_id = DB_ID(N'AdventureWorks');
SET @object_id = OBJECT_ID(N'AdventureWorks.Person.Address');
IF @db_id IS NULL 
  BEGIN;
    PRINT N'Invalid database';
  END;
ELSE IF @object_id IS NULL
  BEGIN;
    PRINT N'Invalid object';
  END;
ELSE
  BEGIN;
    SELECT * FROM sys.dm_db_index_operational_stats(@db_id, @object_id, NULL, NULL);
  END;
GO

Change History

Release	History
17 July 2006	New content: Added the Exceptions section.
14 April 2006	Updated content: Corrected example C.

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