How to Create and Query Linked Database Servers in SQL Server

How do I create and query linked database servers in SQL Server?

You need to use sp_linkedserver to create a linked server.

sp_addlinkedserver [ @server= ] 'server' [ , [ @srvproduct= ] 'product_name' ] 
[ , [ @provider= ] 'provider_name' ]
[ , [ @datasrc= ] 'data_source' ]
[ , [ @location= ] 'location' ]
[ , [ @provstr= ] 'provider_string' ]
[ , [ @catalog= ] 'catalog' ]

More information available on MSDN.

Query tables between two different servers in SQL Server

Another way to query a database hosted in a remote SQL Server is the OPENROWSET T-SQL function. To use the OPENROWSET ad hoc method, you need to provide all connection information that is required to connect to the remote SQL server and many other resources.

Using OPENROWSET requires enabling the Ad Hoc Distributed Queries advanced configuration option same as the OPENDATASOURCE function.

You need to provide the provider’s name, the connection string and the query as follows:

OPENROWSET(‘providername’,’datascource,’query)

SQL Server Linked Server Example Query

The format should probably be:

<server>.<database>.<schema>.<table>

For example:
DatabaseServer1.db1.dbo.table1


Update: I know this is an old question and the answer I have is correct; however, I think any one else stumbling upon this should know a few things.

Namely, when querying against a linked server in a join situation the ENTIRE table from the linked server will likely be downloaded to the server the query is executing from in order to do the join operation. In the OP's case, both table1 from DB1 and table1 from DB2 will be transferred in their entirety to the server executing the query, presumably named DB3.

If you have large tables, this may result in an operation that takes a long time to execute. After all it is now constrained by network traffic speeds which is orders of magnitude slower than memory or even disk transfer speeds.

If possible, perform a single query against the remote server, without joining to a local table, to pull the data you need into a temp table. Then query off of that.

If that's not possible then you need to look at the various things that would cause SQL server to have to load the entire table locally. For example using GETDATE() or even certain joins. Others performance killers include not giving appropriate rights.

See http://thomaslarock.com/2013/05/top-3-performance-killers-for-linked-server-queries/ for some more info.

How to create connection between visual studio and linked server in SQL Server?

You can connect to any database from the list for example connect to first database you have from the list "DB_A4F558_cyanlab" , then you can use the following select statement from visual studio or stored procedure in SQL server:

SELECT * FROM OPENQUERY([CARE] , 'SELECT * from dual');

In this way you can select the data you need from the linked server [CARE] through your database.

Create View using Linked Server db in SQL Server

You need to use the four part qualified name: linkedserver.database.schema.table

SELECT * FROM [1.2.3.4].Northwind.dbo.Customers

Here is an MSDN article about accessing object names.

You might want to try manually creating the view, rather than using the SQL Management tools:

CREATE VIEW [dbo].[sywx]
AS
SELECT *
FROM [1.2.3.4].Atia.dbo.IpPbxDCR
GO

I also recommend that you use a name, if possible, for the linked server rather than using the IP address.

How to execute Union of 2 queries from different SQL Servers?

You need to create the linked server so you have to access of that server after that You can try this way to call and execute the query.

A linked server allows for access to distributed, heterogeneous queries against OLE DB data sources. After a linked server is created, distributed queries can be run against this server, and queries can join tables from more than one data source. If the linked server is defined as an instance of SQL Server, remote stored procedures can be executed.

Select * from <ServerName>.<databaseName>.<SchemaName>.<Table1>

Here is the official documentation to configure the link server.

SSMS - Linked Servers - Azure


I am looking for a way to link these to allow SSMS to query against the MySQL database, which I believe can be done using a linked server in SSMS. The issue is that my SSMS seems to not have the options I would expect existing SSMS Options like Server Objects and linked servers

You cannot.

Azure SQL does not supported Linked Servers. Only on-prem SQL Server and Azure SQL Managed Instance supports that.

https://docs.microsoft.com/en-us/sql/relational-databases/linked-servers/create-linked-servers-sql-server-database-engine?view=sql-server-ver15


However you can use OPENROWSET to query any OLE-DB data-source from Azure SQL but this is not the same as a Linked Server.



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