fix: faster queries for DISTINCT values

Author: fstagni

src/DIRAC/WorkloadManagementSystem/Agent/JobCleaningAgent.py

@@ -87,7 +87,7 @@ def initialize(self):
 
     def _getAllowedJobTypes(self):
         """Get valid jobTypes"""
-        result = self.jobDB.getDistinctJobAttributes("JobType")
+        result = self.jobDB._query("SELECT DISTINCT JobType FROM JobsHistorySummary")
         if not result["OK"]:
             return result
         cleanJobTypes = []

src/DIRAC/WorkloadManagementSystem/DB/JobDB.py

@@ -1197,7 +1197,7 @@ def getSiteSummary(self):
         waitingList = ['"Submitted"', '"Assigned"', '"Waiting"', '"Matched"']
         waitingString = ",".join(waitingList)
 
-        result = self.getDistinctJobAttributes("Site")
+        result = self._query("SELECT DISTINCT Site FROM JobsHistorySummary")
         if not result["OK"]:
             return result