perf: 优化has_envdata的sql查询2

apps/em/views.py

@@ -15,8 +15,8 @@ from django.db import transaction
 from apps.em.services import daoru_equipment
 from rest_framework.response import Response
 from django.conf import settings
-from django.db.models import Count, Case, When, IntegerField, Max, OuterRef, Subquery
+from django.db.models import Count, Case, When, IntegerField
-from datetime import datetime, timedelta
+from apps.enp.services import get_last_envdata
 
 # Create your views here.
 
@@ -75,12 +75,10 @@ class EquipmentViewSet(CustomModelViewSet):
         if self.request.query_params.get("has_envdata", "no") == "yes":
             now = timezone.localtime()
             now_10_before = now - timezone.timedelta(minutes=10)
+            edata_dict = {}
+            if data:
                 data_ids = [item["id"] for item in data]
-            from apps.enp.models import EnvData
+                edata = get_last_envdata(data_ids, now_10_before, now)
-            from apps.enp.serializers import EnvDataSerializer
-
-            edata_qs = EnvData.objects.filter(equipment_id__in=data_ids, timex__gte=now_10_before, timex__lte=now).order_by("timex")
-            edata = EnvDataSerializer(edata_qs, many=True).data
                 edata_dict = {item["equipment"]: item for item in edata}
             for item in data:
                 item["envdata"] = edata_dict.get(item["id"], {})

apps/enp/services.py

@@ -1 +1,26 @@
-from openpyxl import load_workbook
+from apps.enp.models import EnvData
+from apps.enp.serializers import EnvDataSerializer
+from datetime import datetime
+
+def get_last_envdata(eIds: list, time_start: datetime, time_end: datetime):
+    eIds_str = ",".join([f"'{item}'" for item in eIds])  # 将 ID 列表格式化为字符串
+    time_start_str = time_start.strftime("%Y-%m-%d %H:%M:%S")
+    time_end_str = time_end.strftime("%Y-%m-%d %H:%M:%S")
+    esql = f'''
+    SELECT DISTINCT ON (equipment_id) *
+    FROM enp_envdata ee
+    WHERE equipment_id IN ({eIds_str})
+    AND timex AT TIME ZONE 'Asia/Shanghai' >= '{time_start_str}'
+    AND timex AT TIME ZONE 'Asia/Shanghai' <= '{time_end_str}'
+    ORDER BY equipment_id, timex DESC
+    '''
+    edata = EnvDataSerializer(EnvData.objects.raw(esql), many=True).data
+
+    # esql ='''SELECT DISTINCT ON (equipment_id) *
+                #             FROM enp_envdata ee
+                #             WHERE equipment_id IN %s
+                #             AND timex AT TIME ZONE 'Asia/Shanghai' >= %s
+                #             AND timex AT TIME ZONE 'Asia/Shanghai' <= %s
+                #             ORDER BY equipment_id, timex DESC'''
+                # res = query_all_dict(esql, [tuple(data_ids), now_10_before_str, now_str])
+    return edata