使用mysql sum統計函式 結果為null時返回值改為0
阿新 • • 發佈:2019-01-30
//查詢定時任務是否存在 public Integer getPetTime(HomePetTime homePetTime){ Integer result = 0; ConnectionDB util = new ConnectionDB(); Object[] objs =new Object[]{homePetTime.getGateway_id(),homePetTime.getTiming_id()}; List set= util.excuteQuery("select COALESCE(sum(1),0) as times from wlsq_data.home_pet_feeder_timing where gateway_id=? and timing_id=? and del_flag=0 ", objs); if(set !=null && set.size() >0){ for(Object obj:set){ HashMap<String, Object> map =(HashMap<String, Object>)obj; Integer str = Integer.parseInt(map.get("times").toString()); if(str == 0){ result = 0; }else{ result = str; } } } return result; }
重點核心sql:
select COALESCE(sum(1),0) as times from wlsq_data.home_pet_feeder_timing where gateway_id=? and timing_id=? and del_flag=0