DECLARE @Id INT;
    SELECT @Id = id
    FROM sysobjects
    WHERE name = 'TblDrugMind'
IF EXISTS (SELECT * FROM sysobjects WHERE parent_obj=@Id AND xtype='PK')
BEGIN

ALTER TABLE TblDrugMind   DROP CONSTRAINT PK_TblDrug_care
 ALTER TABLE TblDrugMind ALTER COLUMN Mind_Code VARCHAR(9) NOT NULL
  ALTER TABLE TblDrugMind ALTER COLUMN Mind_Name nvarchar(200) NOT NULL
 ALTER TABLE TblDrugMind ADD CONSTRAINT PK_TblDrug_care Primary Key (Mind_Code)   
end