以下為引用的內(nèi)容：

The object 'DF__xxxxxxxxxxx' is dependent on column 'column1'.
ALTER TABLE DROP COLUMN column1failed because one or more objects access this column.

以下為引用的內(nèi)容：

-- this script drops the default constraint which is generated by the setting of default value.
DECLARE @tablename VARCHAR(100), @columnname VARCHAR(100), @tab VARCHAR(100)
SET @tablename='CountryGroupEmailAndWaitAux'
SET @columnname='actionOfHasNoValidEmail'
declare @defname varchar(100)
declare @cmd varchar(100)
select @defname = name
FROM sysobjects so 
JOIN sysconstraints sc
ON so.id = sc.constid
WHERE object_name(so.parent_obj) = @tablename
AND so.xtype = 'D'
AND sc.colid =
(SELECT colid FROM syscolumns
WHERE id = object_id(@tablename) AND
name = @columnname)
select @cmd='alter table '  @tablename  ' drop constraint '  @defname
if @cmd is null print 'No default constraint to drop'
exec (@cmd)