ALTER taable Client
ADD CONSTRAINT FirstName_Check CHECK (DATALENGTH(FirstName) > 0)
GO

ALTER TABLE Client
ADD CONSTRAINT LastNamealter taable Client
ADD CONSTRAINT FirstName_Check CHECK (DATALENGTH(FirstName) > 0)
GO

ALTER TABLE Client
ADD CONSTRAINT LastName_Check CHECK (DATALENGTH(LastName) > 0 AND LastName NOT IN ('Martyniuk', 'Pudzianowski'))
go_Check CHECK (DATALENGTH(LastName) > 0 AND LastName NOT IN ('Martyniuk', 'Pudzianowski'))
GO