Cursor in SQL server

DECLARE @idns VARCHAR(20), @message NVARCHAR(100);
 
DECLARE bts_cursor CURSOR FOR 
 SELECT ISDN FROM CDR.dbo.CDR WHERE BTS_ATT IS NULL ORDER BY CustomerID;

OPEN bts_cursor
FETCH NEXT FROM bts_cursor
INTO @idns
WHILE @@FETCH_STATUS = 0 
BEGIN 
 PRINT ' ' 
    SELECT @message = '----- IDNS: ' + @idns 
    PRINT @message 
 
   select *  FROM  OPENQUERY(CDR ,  'select sub_id,CUST_ID,isdn,sub_name,status,ACT_STATUS,STA_DATETIME,END_DATETIME,REG_TYPE,USER_CREATED,SHOP_CODE,SHOP_SALE,BIRTH_DATE,GENDER,VALID_DATETIME,
 CHANGE_DATETIME,PRODUCT_CODE,DISTRICT_ACTIVE,CENTRE_CODE,CENTRE_SALE,BTS,OWNER_TYPE,OWNER_CODE from report.sub_mb_pre where status = 2 and ACT_STATUS =00' and ISDN = @idns)
 -- Get the next item. 
    FETCH NEXT FROM bts_cursor 
    INTO @idns
END
CLOSE bts_cursor 
DEALLOCATE bts_cursor