Question

I need to add a new column to a table, and the new column should have the same values as an existing column. Is there an easy way to do this? The table doesn’t have that many values so I can probably do it manually if necessary, but there must be a better way.

Answer 1

I would do

ALTER TABLE MyTable
ADD NewColumn int

UPDATE MyTable SET NewColumn = OldColumn

The only problem is with NON NULL columns. You’ll have to provide default value, update and then delete default-value constraint.