SQL SERVER – Rename Logical Database File Name for Any Database

During the recent Comprehensive Database Performance Health Check, we had to restore a database on a server. When we restored a database, we realized that the logical file name of the database was incorrect and we had to change that to something more consistent with the organization’s naming convention. Let us see how we changed logical database file name in a few quick steps. Here is how to rename logical database files safely.

What is Logical Database File Name?

SQL Server database files have two different names – 1) logical file name and 2) physical file name. You can see both the names of the files for your database when you run the following command.

USE SQLAuthority
GO
SELECT file_id, name AS logical_name, physical_name
FROM sys.database_files
GO

When you run above command you will see the following results:

When you want to do any T-SQL related operation, you will have to use the logical name in your SQL Server commands. Some people like to keep the logical filename unique across their SQL Server instance but that is not a requirement from SQL Server

Change the Logical Database File Name

Now let us see a simple script which can change the logical file name.

Please make sure that you select the appropriate database context for your script when you want to change the logical name.

USE [master];
GO
ALTER DATABASE [SQLAuthority] MODIFY FILE ( NAME = SQLAuthority, NEWNAME = SQLAuthority_Data);
GO
ALTER DATABASE [SQLAuthority] MODIFY FILE ( NAME = SQLAuthority_log, NEWNAME = SQLAuthority_Logs);
GO

Once you run the above script, you can once again run the command to check the logical filename and you will find the name of the file is now changed.

You do not have to restart your server to make the change effective.

Well, that’s it, changing the logical database file name is very easy.

Why It Pays to Rename Logical Database Files Consistently

The logical name shows up in more places than people expect. RESTORE ... WITH MOVE needs it to place each file, and DBCC SHRINKFILE and ALTER DATABASE ... MODIFY FILE use it too. When every environment uses the same names, your restore and maintenance scripts work everywhere without edits.

Keep two things in mind. The logical names must be unique within one database. Renaming the logical name does not touch the physical file on disk; if you also want a new physical file name, you have to take the database offline, rename the file, and point SQL Server to it with MODIFY FILE and FILENAME. Check the result any time with SELECT name, physical_name FROM sys.database_files.

Published by Pinal Dave on SQLAuthority. More of my work at pinaldave.com.