SQL語句：select distinct a.device_hash, sum(b.cmn_merge_count) from (select distinct device_hash from tbl_fileprotect_svc_instance where customer_id='3f500ac5-020d-3ce3-a2a2-51a59ddd606e') as a left join tbl_file_protect_alarm as b on a.device_hash = b.device_hash group by a.device_hash; 簡化SQL如下（把子查詢轉(zhuǎn)化為WHERE語句）：復(fù)制代碼 select distinct a.device_hash, sum(b.cmn_merge_count) from tbl_fileprotect_svc_instance as a left join tbl_file_protect_alarm as b on a.device_hash = b.device_hash where a.customer_id='3f500ac5-020d-3ce3-a2a2-51a59ddd606e' group by a.device_hash;select distinct a.device_hash, sum(b.cmn_merge_count) from tbl_fileprotect_svc_instance as a left join tbl_file_protect_alarm as b on a.device_hash = b.device_hash where a.customer_id='3f500ac5-020d-3ce3-a2a2-51a59ddd606e' group by a.device_hash;select distinct a.device_hash, sum(b.cmn_merge_count) as alarm_sum from tbl_fileprotect_svc_instance as a left join tbl_file_protect_alarm as b on a.device_hash = b.device_hash where a.customer_id='3f500ac5-020d-3ce3-a2a2-51a59ddd606e' group by a.device_hash; 復(fù)制代碼Django代碼：復(fù)制代碼 TODO： 方法一： ret = [] device_list = models.FILE_PROTECT_INSTANCE.objects.filter(customer_id=customer_id) for item in device_list:tmp_dict = {}tmp_dict['device_hash'] = item.device_hashtmp_dict['hostname'] = item.hostnametmp_dict['status'] = item.status from django.db.models import Sumalarm_sum_group_items = models.FILE_PROTECT_ALARM.objects.filter(customer_id=customer_id).filter(device_hash=tmp_dict['device_hash']).values('device_hash').annotate(alarm_sum=Sum('cmn_merge_count'))#tmp_dict['customer_id'] = customer_idtmp_dict['alarm_sum'] = alarm_sum_group_items[0]['alarm_sum'] if (len(alarm_sum_group_items)!=0) else 0ret.append(tmp_dict) 復(fù)制代碼方法二：hashes = A.objects.values_list("device_hash", flat=True).filter(customer_id="3f500ac5-020d-3ce3-a2a2-51a59ddd606e")B.objects.filter(device_hash__in=hashes).values_list("device_hash").annotate(Sum("cmn_merge_count"))SQL實(shí)現(xiàn)聚合查詢統(tǒng)計(jì)（Sum，Count等）復(fù)制代碼 from django.db.models import Sum#start_time = datetime.utcfromtimestamp(data['start_time']).replace(tzinfo=utc)#end_time = datetime.utcfromtimestamp(data['end_time']).replace(tzinfo=utc)end_time = datetime.now()start_time = end_time + timedelta(days=-1)condition['cmn_alert_time__range'] = (start_time, end_time)#alarm_sum_group_items_day = models.FILE_PROTECT_ALARM.objects.filter(**condition).values('customer_id').annotate(alarm_sum_day=Sum('cmn_merge_count'))alarm_sum_day = models.FILE_PROTECT_ALARM.objects.filter(**condition).aggregate(Sum("cmn_merge_count"))day_sum = alarm_sum_day['cmn_merge_count__sum'] if (alarm_sum_day['cmn_merge_count__sum'] is not None) else 0 end_time = datetime.now()start_time = end_time + timedelta(days=-7)condition['cmn_alert_time__range'] = (start_time, end_time)#alarm_sum_group_items_week = models.FILE_PROTECT_ALARM.objects.filter(**condition).values('customer_id').annotate(alarm_sum_week=Sum('cmn_merge_count'))alarm_sum_week = models.FILE_PROTECT_ALARM.objects.filter(**condition).aggregate(Sum("cmn_merge_count"))week_sum = alarm_sum_week['cmn_merge_count__sum'] if (alarm_sum_week['cmn_merge_count__sum'] is not None) else 0 condition = {}#condition['device_hash'] = data['device_hash']condition['customer_id'] = customer_idend_time = datetime.now()#start_time = end_time + timedelta(days=-7)condition['cmn_alert_time__lte'] = end_time#alarm_sum_group_items_all = models.FILE_PROTECT_ALARM.objects.filter(**condition).values('customer_id').annotate(alarm_sum_all=Sum('cmn_merge_count'))alarm_sum_all = models.FILE_PROTECT_ALARM.objects.filter(**condition).aggregate(Sum("cmn_merge_count"))all_sum = alarm_sum_all['cmn_merge_count__sum'] if (alarm_sum_all['cmn_merge_count__sum'] is not None) else 0 參考資料： http://stackoverflow.com/questions/6481279/django-sum-query

　　

轉(zhuǎn)載于:https://www.cnblogs.com/pyxiaomangshe/p/7741612.html

總結(jié)

以上是生活随笔為你收集整理的Django 如何实现 如下 联表 JOIN 查询？的全部內(nèi)容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網(wǎng)站內(nèi)容還不錯(cuò)，歡迎將生活随笔推薦給好友。