USE [test]
GO

Alter PROCEDURE dbo.CreateUser
@loginName nvarchar(100),
@userName nvarchar(100) ,
@schemaName nvarchar(10)


AS
SET NOCOUNT ON;

IF NOT EXISTS (SELECT [name] FROM [sys].[database_principals] WHERE [type] = N'S' AND [name] = @loginName)
BEGIN

CREATE LOGIN [@loginName] WITH PASSWORD=N'123', DEFAULT_DATABASE=[test], CHECK_EXPIRATION=OFF, CHECK_POLICY=OFF
Create USER [@userName] for login [@loginName]
GRANT SELECT, INSERT, UPDATE, DELETE ON SCHEMA :: [dbo]  to [@userName]
GRANT SELECT, INSERT, UPDATE, DELETE ON SCHEMA :: [@schemaName]  to [@userName]

END