Add column to SQL Server

Question

I need to add a column to my SQL Server table. Is it possible to do so without losing the data, I already have?

Answer 1

Add new column to Table

ALTER TABLE [table]
ADD Column1 Datatype

E.g

ALTER TABLE [test]
ADD ID Int

If User wants to make it auto incremented then

ALTER TABLE [test]
ADD ID Int IDENTITY(1,1) NOT NULL