How to drop column with constraint?

Question

How to drop a column which is having Default constraint in SQL Server 2008?

My query is

alter table tbloffers
drop column checkin

Answer 1

Here's another way to drop a default constraint with an unknown name without having to first run a separate query to get the constraint name:

DECLARE @ConstraintName nvarchar(200)
SELECT @ConstraintName = Name FROM SYS.DEFAULT_CONSTRAINTS
WHERE PARENT_OBJECT_ID = OBJECT_ID('__TableName__')
AND PARENT_COLUMN_ID = (SELECT column_id FROM sys.columns
                        WHERE NAME = N'__ColumnName__'
                        AND object_id = OBJECT_ID(N'__TableName__'))
IF @ConstraintName IS NOT NULL
EXEC('ALTER TABLE __TableName__ DROP CONSTRAINT ' + @ConstraintName)