SQL Server Script to create a new user

Question

Based on your question, I think that you may be a bit confused about the difference between a User and a Login. A Login is an account on the SQL Server as a whole - someone who is able to log in to the server and who has a password. A User is a Login with access to a specific database.

Creating a Login is easy and must (obviously) be done before creating a User account for the login in a specific database:

CREATE LOGIN NewAdminName WITH PASSWORD = 'ABCD'
GO

Here is how you create a User with db_owner privileges using the Login you just declared:

Use YourDatabase;
GO

IF NOT EXISTS (SELECT * FROM sys.database_principals WHERE name = N'NewAdminName')
BEGIN
    CREATE USER [NewAdminName] FOR LOGIN [NewAdminName]
    EXEC sp_addrolemember N'db_owner', N'NewAdminName'
END;
GO

Now, Logins are a bit more fluid than I make it seem above. For example, a Login account is automatically created (in most SQL Server installations) for the Windows Administrator account when the database is installed. In most situations, I just use that when I am administering a database (it has all privileges).

However, if you are going to be accessing the SQL Server from an application, then you will want to set the server up for "Mixed Mode" (both Windows and SQL logins) and create a Login as shown above. You'll then "GRANT" priviliges to that SQL Login based on what is needed for your app. See here for more information.

UPDATE: Aaron points out the use of the sp_addsrvrolemember to assign a prepared role to your login account. This is a good idea - faster and easier than manually granting privileges. If you google it you'll see plenty of links. However, you must still understand the distinction between a login and a user.

Full admin rights for the whole server, or a specific database? I think the others answered for a database, but for the server:

USE [master];
GO
CREATE LOGIN MyNewAdminUser 
    WITH PASSWORD    = N'abcd',
    CHECK_POLICY     = OFF,
    CHECK_EXPIRATION = OFF;
GO
EXEC sp_addsrvrolemember 
    @loginame = N'MyNewAdminUser', 
    @rolename = N'sysadmin';

You may need to leave off the CHECK_ parameters depending on what version of SQL Server Express you are using (it is almost always useful to include this information in your question).

If you want to create a generic script you can do it with an Execute statement with a Replace with your username and database name

Declare @userName as varchar(50); 
Declare @defaultDataBaseName as varchar(50);
Declare @LoginCreationScript as varchar(max);
Declare @UserCreationScript as varchar(max);
Declare @TempUserCreationScript as varchar(max);
set @defaultDataBaseName = 'data1';
set @userName = 'domain\userName';
set @LoginCreationScript ='CREATE LOGIN [{userName}]
FROM WINDOWS 
WITH DEFAULT_DATABASE ={dataBaseName}'

set @UserCreationScript ='
USE {dataBaseName}
CREATE User [{userName}] for LOGIN [{userName}];
EXEC sp_addrolemember ''db_datareader'', ''{userName}'';
EXEC sp_addrolemember ''db_datawriter'', ''{userName}'';
Grant Execute on Schema :: dbo TO [{userName}];'
/*Login creation*/
set @LoginCreationScript=Replace(Replace(@LoginCreationScript, '{userName}', @userName), '{dataBaseName}', @defaultDataBaseName)
set @UserCreationScript =Replace(@UserCreationScript, '{userName}', @userName)
Execute(@LoginCreationScript)

/*User creation and role assignment*/
set @TempUserCreationScript =Replace(@UserCreationScript, '{dataBaseName}', @defaultDataBaseName)
Execute(@TempUserCreationScript)
set @TempUserCreationScript =Replace(@UserCreationScript, '{dataBaseName}', 'db2')
Execute(@TempUserCreationScript)
set @TempUserCreationScript =Replace(@UserCreationScript, '{dataBaseName}', 'db3')
Execute(@TempUserCreationScript)

You can use:

CREATE LOGIN <login name> WITH PASSWORD = '<password>' ; GO 

To create the login (See here for more details).

Then you may need to use:

CREATE USER user_name 

To create the user associated with the login for the specific database you want to grant them access too.

(See here for details)

You can also use:

GRANT permission  [ ,...n ] ON SCHEMA :: schema_name

To set up the permissions for the schema's that you assigned the users to.

(See here for details)

Two other commands you might find useful are ALTER USER and ALTER LOGIN.

CREATE LOGIN AdminLOGIN WITH PASSWORD = 'pass'
GO


Use MyDatabase;
GO

IF NOT EXISTS (SELECT * FROM sys.database_principals WHERE name = N'AdminLOGIN')
BEGIN
    CREATE USER [AdminLOGIN] FOR LOGIN [AdminLOGIN]
    EXEC sp_addrolemember N'db_owner', N'AdminLOGIN'
    EXEC master..sp_addsrvrolemember @loginame = N'adminlogin', @rolename = N'sysadmin'
END;
GO

this full help you for network using:

1- Right-click on SQL Server instance at root of Object Explorer, click on Properties
Select Security from the left pane.

2- Select the SQL Server and Windows Authentication mode radio button, and click OK.

3- Right-click on the SQL Server instance, select Restart (alternatively, open up Services and restart the SQL Server service).

4- Close sql server application and reopen it

5- open 'SQL Server Configuration Manager' and tcp enabled for network

6-Double-click the TCP/IP protocol, go to the IP Addresses tab and scroll down to the IPAll section.

7-Specify the 1433 in the TCP Port field (or another port if 1433 is used by another MSSQL Server) and press the OK 

8-Open in Sql Server: Security And Login  And Right Click on Login Name And Select Peroperties And Select Server Roles And 
  Checked The Sysadmin And Bulkadmin then Ok.
9-firewall: Open cmd as administrator and type: 
      netsh firewall set portopening protocol = TCP port = 1433 name = SQLPort mode = ENABLE scope = SUBNET profile = CURRENT