In this post, I am sharing two different scripts to populate attach and detach scripts for all your SQL Server Databases.

When we are migrating our SQL Database Server, we require to move all databases from one server to another server.

If you have a big number of databases, making of individual attach and detach script will take more time.

I have also added script to change database access mode like: Multi_User to Single_User for Detach Process and Single_User to Multi_User for Attach Process.

If your database is in use, you may require to change the database access mode to close all running connections.

Using this script you can populate attach and detach scripts for all databases.
Execute this script to generate detach scripts for all databases:

DECLARE @DatabaseName AS VARCHAR(255)
DECLARE CurDetach CURSOR FOR
  
  SELECT name
  FROM   MASTER.sys.databases
  WHERE  owner_sid > 1;

OPEN CurDetach
FETCH Next FROM CurDetach INTO @DatabaseName
WHILE @@FETCH_STATUS = 0
  BEGIN      
	  PRINT 
		'ALTER DATABASE ' + @DatabaseName + ' SET SINGLE_USER WITH ROLLBACK IMMEDIATE' 
		+ CHAR(10) + ' GO' + CHAR(10) +
		'sp_detach_db ' + @DatabaseName + CHAR(10)
		+ ' GO' + CHAR(10) + 'Print ''Detach of '
		+ @DatabaseName
		+ ' database completed successfully'''
		+ CHAR(10) + ' GO'

      FETCH NEXT FROM CurDetach INTO @DatabaseName
  END

CLOSE CurDetach
DEALLOCATE CurDetach

Execute this script to generate attach scripts for all databases:
You can change your file name or file path using @Filepath variable.

DECLARE @DatabaseName AS VARCHAR(255)
DECLARE @Filepath AS VARCHAR(255)

SET @Filepath = 'C:\SQLDATA\'

DECLARE CurAttach CURSOR FOR
  SELECT name
  FROM   MASTER.sys.databases
  WHERE  owner_sid > 1;

OPEN CurAttach
FETCH Next FROM CurAttach INTO @DatabaseName
WHILE @@FETCH_STATUS = 0
  BEGIN      
	  PRINT 
		'CREATE DATABASE ' + @DatabaseName + ' ON
		(FILENAME = '+ @Filepath + @DatabaseName +'.mdf)
		,(FILENAME = '+ @Filepath + @DatabaseName +'.ldf)
		FOR ATTACH
		GO

		ALTER DATABASE '+ @DatabaseName +' SET MULTI_USER WITH ROLLBACK IMMEDIATE
		GO'
      FETCH NEXT FROM CurAttach INTO @DatabaseName
  END

CLOSE CurAttach
DEALLOCATE CurAttach

If you are a beginner for SQL DBA profile, an interviewer may as this question like What is the difference between SINGLE_USER, RESTRICTED_USER and MULTI_USER in SQL Server.

If you confuse and want to give your answer in one line, you can say like These are the ALTER DATABASE SET commands which we can use to get exclusive access to SQL Server Database.

SINGLE_USER: Only one user can connect to the database at a time

ALTER DATABASE Database_Name 
SET SINGLE_USER WITH ROLLBACK IMMEDIATE
GO

RESTRICTED_USER: Only DB_OWNER, DB_CREATOR or SYSADMIN roles can connect to the database

ALTER DATABASE Database_Name 
SET RESTRICTED_USER WITH ROLLBACK IMMEDIATE
GO

MULTI_USER: Any number of users can connect to the database

ALTER DATABASE Database_Name 
SET MULTI_USER 
GO

In this post, I am sharing scripts to kill all your running processes or sessions of SQL Server.

DBA always set time of database maintenance activities, but sometimes they find few running sessions so they require closing all connections of a SQL Server Database.

Before executing this script, please take care and verify all running connections and processes otherwise this script will harm to your data.

You require this type of script very occasionally, but I am sharing here because this is also one of the important scripts for SQL DBA.

How to find running sessions or processes in SQL Server?

Script to find Running Process and Session in SQL Server

Command to Kill particular session_id:

KILL 'session_id'

Script to kill multiple sessions:

DECLARE @DatabaseName nvarchar(50)
SET @DatabaseName = 'dbrnd'

DECLARE @SQL varchar(max)
SET @SQL = ''

SELECT @SQL = @SQL + 'Kill ' + Convert(varchar, SPId) + ';'
FROM MASTER..SysProcesses
WHERE DBId = DB_ID(@DatabaseName) AND SPId <> @@SPId

EXEC(@SQL)

Change your database mode from multi-user to single-user:

Once you change the database mode from multi-user to single-user, SQL Server immediately stops all the connections of the database. No one can connect to that database.

The DBA can perform the maintenance activity and after that, they can again change the database mode from single-user to multi-user.

To set Single User:

ALTER DATABASE [Database_Name] SET SINGLE_USER WITH ROLLBACK IMMEDIATE

To set Multi User:

ALTER DATABASE [Database_Name] SET MULTI_USER WITH ROLLBACK IMMEDIATE