Смените подачу, чтобы не нулевать
ALTER TABLE
clients
ALTER COLUMN
phone
NVARCHAR(20) NOT NULL;
Grumpy Gibbon
ALTER TABLE
clients
ALTER COLUMN
phone
NVARCHAR(20) NOT NULL;
ALTER TABLE Customer
ALTER COLUMN CustDesc NVARCHAR(MAX) NULL; ALTER TABLE [ExampleTable] ALTER COLUMN [ExampleColumn] INT NULLALTER TABLE YourTable
ADD Foo INT NULL /*Adds a new int column existing rows will be
given a NULL value for the new column*/