Telefonnummer SQL
phone varchar(15) NOT NULL UNIQUE,
-- Here is a good column for phone number with datatype varchar(15)
Blue Bear
phone varchar(15) NOT NULL UNIQUE,
-- Here is a good column for phone number with datatype varchar(15)create table MyTable
(
PhoneNumber char(10)
constraint CK_MyTable_PhoneNumber check (PhoneNumber like '[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]')
)Phone number can be INT and also you type as varchar