--ACARI 
declare @CNTNAME NVARCHAR(100),@SQL NVARCHAR(MAX)
select @CNTNAME=name from sys.default_constraints where name like 'DF__ACARI__DovizBaki%'
SET @SQL='ALTER TABLE [dbo].[ACARI] DROP CONSTRAINT ['+ CONVERT(VARCHAR(100),@CNTNAME)+']'
EXEC(@SQL)
ALTER TABLE [dbo].[ACARI] drop column [DovizBakiye]