IF  EXISTS (SELECT name FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[DF_Trackingprescription_StationNo]') AND type = 'D')
BEGIN
   ALTER TABLE [dbo].[TrackingPrescription] DROP CONSTRAINT [DF_Trackingprescription_StationNo]
END

 
 IF  EXISTS(SELECT name FROM sysobjects  WHERE name = 'TrackingPrescription')
 BEGIN
ALTER TABLE dbo.TrackingPrescription ALTER COLUMN StationNo SMALLINT NULL  
ALTER TABLE [dbo].[TrackingPrescription] ADD  CONSTRAINT [DF_Trackingprescription_StationNo]  DEFAULT ((0)) FOR [StationNo]
ALTER TABLE dbo.TrackingPrescription ALTER COLUMN [Status] TINYINT  NULL
ALTER TABLE dbo.TrackingPrescription ALTER COLUMN prescriptionId UNIQUEIDENTIFIER NULL 
ALTER TABLE dbo.TrackingPrescription ALTER COLUMN userId SMALLINT NULL
END