sql server column definition default value on if null code example

Example 1: alter column to not null with default value sql server

ALTER TABLE SomeTable
        ADD SomeCol Bit NULL --Or NOT NULL.
 CONSTRAINT D_SomeTable_SomeCol --When Omitted a Default-Constraint Name is autogenerated.
    DEFAULT (0)--Optional Default-Constraint.
WITH VALUES --Add if Column is Nullable and you want the Default Value for Existing Records.

Example 2: how to check default value of column in sql server

SELECT object_definition(default_object_id) AS definition
FROM   sys.columns
WHERE  name      ='colname'
AND    object_id = object_id('dbo.tablename')