def testNetworkCostDenormalization(self):
"""Check network cost for queries that reference denormalized collections"""
# Get the "base" design cost when all of the collections
# are sharded on their "interesting" fields
d0 = Design()
for i in xrange(len(CostModelTestCase.COLLECTION_NAMES)):
col_info = self.collections[CostModelTestCase.COLLECTION_NAMES[i]]
d0.addCollection(col_info['name'])
if i == 0:
d0.addShardKey(col_info['name'], col_info['interesting'])
else:
d0.addShardKey(col_info['name'], ["_id"])
self.cm.invalidateCache(d0, col_info['name'])
## FOR
self.cm.reset()
self.state.reset()
cost0 = self.cm.getCost(d0)
print "cost0:", cost0
# Now get the network cost for when we denormalize the
# second collection inside of the first one
# We should have a lower cost because there should now be fewer queries
d1 = Design()
for i in xrange(0, len(CostModelTestCase.COLLECTION_NAMES)):
col_info = self.collections[CostModelTestCase.COLLECTION_NAMES[i]]
self.assertTrue(col_info['interesting'])
d1.addCollection(col_info['name'])
if i == 0:
d1.addShardKey(col_info['name'], col_info['interesting'])
else:
parent = self.collections[CostModelTestCase.COLLECTION_NAMES[0]]
self.assertIsNotNone(parent)
d1.setDenormalizationParent(col_info['name'], parent['name'])
self.assertTrue(d1.isDenormalized(col_info['name']), col_info['name'])
self.assertIsNotNone(d1.getDenormalizationParent(col_info['name']))
self.cm.invalidateCache(d1, col_info['name'])
combiner = WorkloadCombiner(self.collections, self.workload)
combinedWorkload = combiner.process(d1)
self.state.updateWorkload(combinedWorkload)
self.cm.reset()
self.state.reset()
cost1 = self.cm.getCost(d1)
print "cost1:", cost1
self.assertLess(cost1, cost0)
# The denormalization cost should also be the same as the cost
# when we remove all of the ops one the second collection
backup_collections = copy.deepcopy(self.collections)
for sess in self.state.workload:
for op in sess["operations"]:
if op["collection"] <> CostModelTestCase.COLLECTION_NAMES[0]:
sess["operations"].remove(op)
## FOR (op)
## FOR (sess)
for i in xrange(1, len(CostModelTestCase.COLLECTION_NAMES)):
del self.collections[CostModelTestCase.COLLECTION_NAMES[i]]
print "deleted name: ", CostModelTestCase.COLLECTION_NAMES[i]
self.cm.reset()
self.state.reset()
cost2 = self.cm.getCost(d1)
print "cost2:", cost2
self.assertEqual(cost1, cost2)
# Restore the original workload and see if the cost remains the same with the original one
self.state.restoreOriginalWorkload()
self.state.collections = backup_collections
self.cm.reset()
self.state.reset()
cost3 = self.cm.getCost(d0)
print "cost3:", cost3
self.assertEqual(cost3, cost0)
