SQL Server 2005 drop column with constraints

Question

I have a column with a \"DEFAULT\" constraint. I\'d like to create a script that drops that column.

The problem is that it returns this error:

Msg 50         


        

Answer 1

Perhaps it could help a little more:

declare @tablename nvarchar(200)
declare @colname nvarchar(200)
declare @default sysname, @sql nvarchar(max)

set @tablename = 'your table'
set @colname = 'column to drop'

select @default = name 
from sys.default_constraints 
where parent_object_id = object_id(@tablename)
AND type = 'D'
AND parent_column_id = (
    select column_id 
    from sys.columns 
    where object_id = object_id(@tablename)
    and name = @colname 
    )

set @sql = N'alter table ' + @tablename + ' drop constraint ' + @default
exec sp_executesql @sql

set @sql = N'alter table ' + @tablename + ' drop column ' + @colname
exec sp_executesql @sql

Only need to set the @tablename & @colname variables to drop the column.