Can I Query Columns from Multiple Databases on the Same Server?

Selecting Columns Across Different Databases

Is it feasible to perform a select query that spans across different databases residing on the same server? If so, what are the steps involved?

Answer:

Yes, it is possible to query columns from multiple databases within the same server. To achieve this, use the syntax databasename.tablename to specify the database.

Example:

Consider the following query that selects the UserID column from two separate databases, mydatabase1 and mydatabse2, and joins them on the UserID field:

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

By using this syntax, you can easily select columns from different databases and combine them in a single query. This provides a convenient way to integrate data from various sources within the same server environment.

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