SQL Server Script to Manage Server LOGIN & Database USER

-- =======================================================================
-- SQL SCRIPT to create LOGIN in the SERVER, and assign sysadmin role to it.
-- =======================================================================
use master
go

if exists (select * from sys.server_principals where type = 'S' and name ='logic')
 drop login [logic]
go
create login [logic] with password=N'123', default_database = [test]
go
exec sp_addsrvrolemember 'logic','sysadmin'

-- =======================================================================
-- SQL SCRIPT to create LOGIN 'comet' in the SERVER.
-- =======================================================================
use master
go

if exists (select * from sys.server_principals where type = 'S' and name ='comet')
 drop login [comet]
go
create login [comet] with password=N'123', default_database = [test]
go

-- =======================================================================
-- SQL SCRIPT to create DATABASE USER linked to the existing
-- SERVER LOGIN in Test Database. And then assign db_owner role to this
-- database user 'db_comet'.
-- =======================================================================
use test
go

if exists (select * from sys.database_principals where type = 'S' and name ='db_comet')
 drop user [db_comet]
go
create user [db_comet] for login [comet] with default_schema = [dbo]
go
exec sp_addrolemember 'db_owner', [db_comet]
go