Modify table: How to change 'Allow Nulls' attribute from not null to allow null

Question

How to change one attribute in a table using T-SQL to allow nulls (not null --> null)? Alter table maybe?

Answer 1

Yes you can use ALTER TABLE as follows:

ALTER TABLE [table name] ALTER COLUMN [column name] [data type] NULL

Quoting from the ALTER TABLE documentation:

NULL can be specified in ALTER COLUMN to force a NOT NULL column to allow null values, except for columns in PRIMARY KEY constraints.