Can SQL Queries Access Data from Multiple Databases on the Same Server?

Querying Data from Multiple Databases

Can SQL queries span multiple databases residing on the same server? Let's explore this possibility.

Answer:

Yes, it is possible to execute SELECT (or INSERT) statements across different databases within the same server. This is achieved by explicitly specifying the database name in the query syntax:

databasename.tablename

Example:

To select the UserID column from the tblUsers table in both mydatabase1 and mydatabase2, use the following query:

SELECT 
    mydatabase1.tblUsers.UserID, 
    mydatabse2.tblUsers.UserID
FROM 
   mydatabase1.tblUsers
       INNER JOIN mydatabase2.tblUsers 
           ON mydatabase1.tblUsers.UserID = mydatabase2.tblUsers.UserID

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