LinkedServer Object (SQL-DMO)

The LinkedServer object exposes the properties of an OLE DB data source, and allows directed Transact-SQL queries against defined data sources.

Remarks

Microsoft® SQL Server™ supports Transact-SQL queries against data stored in one or more SQL Server and heterogeneous databases. SQL Server distributed queries use OLE DB to access a nonlocal data store.

OLE DB defines a provider as an OLE DB component that can deliver data from a store. Typically, OLE DB providers can discriminate among applicable, available data stores. OLE DB defines a data source as that information necessary for the successful delivery of data from the store (such as a user identifier and password).

SQL Server implements persistent storage of an OLE DB provider name and data source definition called a linked server.

With the LinkedServer object, you can:

• Create an OLE DB data source definition, usable as a data provider for a distributed query.
• List the tables of a data source, or the columns contained in a data source table.
• Execute a Transact-SQL statement against a SQL Server OLE DB data source.
• Remove existing data source defining records.

The Name property of a LinkedServer object uses the SQL Server data type sysname. The value of the Name property must be unique within a server running SQL Server.

To create a linked server

1. Create a LinkedServer object.
2. Set the Name property.
3. Set the ProviderName property to indicate the OLE DB provider. For more information about providers available for SQL Server, see OLE DB Providers Tested with SQL Server.
4. Set any additional property values required by the provider. For more information about provider-required values, see your documentation for the OLE DB provider.
5. Add the LinkedServer object to the LinkedServers collection of a connected SQLServer object.

Note When a linked server is created, SQL Server creates a default linked server login record. When using SQL-DMO to create a linked server, adding the LinkedServer object to its containing collection creates the linked server and the default linked server login. The object’s LinkedServerLogins collection contains one member. For more information about the default linked server login created, see sp_addlinkedsrvlogin.

Methods

Properties