USE [master]
GO
CREATE LOGIN [User_Customer]
WITH PASSWORD=N'Strong_Pass',
DEFAULT_DATABASE=[Customer_DB],
CHECK_EXPIRATION=OFF, CHECK_POLICY=OFF
GO

ALTER SERVER ROLE [bulkadmin] ADD MEMBER [Customer_DB]--BULK
GO

USE Customer_DB
GO
CREATE USER [User_Customer]     FOR LOGIN [User_Customer] --User
GO
ALTER ROLE [db_datareader] ADD MEMBER [User_Customer] --DR
GO
ALTER ROLE [db_datawriter] ADD MEMBER [User_Customer] --DW
GO
ALTER ROLE [db_ddladmin]   ADD MEMBER [User_Customer] --DDL
GO
GRANT EXECUTE TO [User_Customer] --EXECUTE
GO
USE [master]
GO
DENY VIEW ANY database to [User_Customer] --DENY

create role MyCustomRole;

ALTER ROLE [db_datareader] ADD MEMBER MyCustomRole--[User_Customer] --DR
GO
ALTER ROLE [db_datawriter] ADD MEMBER MyCustomRole--[User_Customer] --DW
GO
ALTER ROLE [db_ddladmin]   ADD MEMBER MyCustomRole--[User_Customer] --DDL
GO
GRANT EXECUTE TO MyCustomRole--[User_Customer] --EXECUTE
GO

alter role MyCustomRole add member [User_Customer];

execute as user = 'User_Customer';

select *
from sys.fn_my_permissions(null, 'database');

revert;