Skip to main content

Single_user and Multi_user


It is often necessary to change the database to single user mode, especially if you are a DBA. A simple example would be to change the collation settings or any DB settings. The single user will allow only one  user ( usually DBA) to access the database. Hence it will be easy to make changes without the worry of deadlocks or any other type of contention for DB and also without affecting the users.
It is very easy to change the database to Single user mode; in fact, it is just an execution of the script away. Use the script below to change the mode.
ALTER  DATABASE <>  SET SINGLE_USER  WITH NO_WAIT
The NO_WAIT clause will set it to single user mode as soon as you execute the query.  Analternate to this is by using the system stored procedure sp_dboption
EXEC   SP_DBOPTION   <<Data base Name>>,‘SINGLE USER’ ,False
You need to however set the database  back to multi user mode for other users to use it. Without that, it won’t be accessible by others.
Here is the script to set the database to multiuser mode.
ALTER  DATABASE <>   SET MULTI_USER  WITH NO_WAIT
Or the alternate
EXEC   SP_DBOPTION   <>,‘SINGLE USER’ ,False
Maintain caution while changing database to single user mode, as it would disconnect the users already connected to the database.

Comments

Popular posts from this blog

Insufficient access rights to perform the operation. (Exception from HRESULT: 0x80072098)

While accessing the active directory (AD) and authorization manager (AZMAN) , If you get “   Insufficient access rights to perform the operation. (Exception from HRESULT: 0x80072098)  “ message check the    account that is being used to get the LDAP query from AD .  ERROR DETAILS Exception Details:  System.Runtime.InteropServices.COMException: Insufficient access rights to perform the operation. (Exception from HRESULT: 0x80072098) Source Error: Line 154:    'Session("FullName") = System.Security.Principal.WindowsIdentity.GetCurrent.Name.ToString() Line 155: Line 156:    If Not User.IsInRole("Role1") Then Line 157:          Response.Redirect("./Login.aspx") Line 158:    End If  Stack Trace : .... SOLVE IT Steps to do check the app pool rights: Click on the website name that you are having problem with in IIS  In the right panel you will see 'Basic Settings'. Click It. Select the specific pool option and enter the name of the ac

Sql Server database Read_Only / Read_Write

The ALTER DATABASE command allows a database administrator to modify SQL Server databases and their files and filegroups. This includes permitting the changing of database configuration options. Why Read Only ? When you need to ensure that the data is a database is not modified by any users or automated processes, it is useful to set the database into a read-only mode. Once read-only, the data can be read normally but any attempts to create, updated or delete table rows is disallowed. This makes the read-only mode ideal when preparing for data migration, performing data integrity checking or when the data is only required for historical reporting purposes. Make Database Read Only USE  [master] GO ALTER DATABASE  [TESTDB]  SET  READ_ONLY  WITH  NO_WAIT GO Make Database Read/Write USE  [master] GO ALTER DATABASE  [TESTDB]  SET  READ_WRITE  WITH  NO_WAIT GO In case you get the following error message make the database single user: Msg 5070, Level 16, Stat

Do's and Don't SQL

Do's: Writing comments whenever something is not very obvious, as it won’t impact the performance.  (--) for single line  (/*…*/) to mark a section Use proper indentation Use Upper Case for all SQL keywords. SELECT, UPDATE, INSERT, WHERE, INNER JOIN, AND, OR, LIKE. Use BEGIN... END block for multiple statements in conditional code  Use Declare and Set in beginning of Stored procedure Create objects in same database where its relevant table exists otherwise it will reduce network performance. Use PRIMARY key in WHERE condition of UPDATE or DELETE statements as this will avoid error possibilities. If User table references Employee table than the column name used in reference should be UserID where User is table name and ID primary column of User table and UserID is reference column of Employee table. Use select column name instead of select * Use CTE (Common Table Expression); its scope is limited to the next statement in SQL query, instead of temporary tables and der