PYTHON-990 - Support partial indexes

Author: aherlihy

pymongo/collection.py

@@ -1239,6 +1239,8 @@ def create_index(self, keys, **kwargs):
  collection. MongoDB will automatically delete documents from
  this collection after <int> seconds. The indexed field must
  be a UTC datetime or the data will not expire.
+ - `partialFilterExpression`: A document that specifies a filter for
+ a partial index.
 
  See the MongoDB documentation for a full list of supported options by
  server version.
@@ -1248,6 +1250,7 @@ def create_index(self, keys, **kwargs):
  using the option will fail if a duplicate value is detected.
 
  .. note:: `expireAfterSeconds` requires server version **>= 2.2**
+ .. note:: `partialFilterIndexes` requires server version **>= 3.2**
 
  :Parameters:
  - `keys`: a single key or a list of (key, direction)
@@ -1256,6 +1259,8 @@ def create_index(self, keys, **kwargs):
  options (see the above list) should be passed as keyword
  arguments
 
+ .. versionchanged:: 3.2
+ Added partialFilterExpression to support partial indexes.
  .. versionchanged:: 3.0
  Renamed `key_or_list` to `keys`. Removed the `cache_for` option.
  :meth:`create_index` no longer caches index names. Removed support

pymongo/operations.py

@@ -222,16 +222,23 @@ def __init__(self, keys, **kwargs):
  collection. MongoDB will automatically delete documents from
  this collection after <int> seconds. The indexed field must
  be a UTC datetime or the data will not expire.
+ - `partialFilterExpression`: A document that specifies a filter for
+ a partial index.
 
  See the MongoDB documentation for a full list of supported options by
  server version.
 
+ .. note:: `partialFilterIndexes` requires server version **>= 3.2**
+
  :Parameters:
  - `keys`: a single key or a list of (key, direction)
  pairs specifying the index to create
  - `**kwargs` (optional): any additional index creation
  options (see the above list) should be passed as keyword
  arguments
+
+ .. versionchanged:: 3.2
+ Added partialFilterExpression to support partial indexes.
  """
  keys = _index_list(keys)
  if "name" not in kwargs:

test/test_collection.py

@@ -481,6 +481,59 @@ def test_create():
  # Index wasn't created, only the default index on _id
  self.assertEqual(1, len(db.test.index_information()))
 
+ @client_context.require_version_min(3, 1, 9, -1)
+ def test_index_filter(self):
+ db = self.db
+ db.drop_collection("test")
+
+ # Test bad filter spec on create.
+ self.assertRaises(OperationFailure, db.test.create_index, "x",
+ partialFilterExpression=5)
+ self.assertRaises(OperationFailure, db.test.create_index, "x",
+ partialFilterExpression={"x": {"$asdasd": 3}})
+ self.assertRaises(OperationFailure, db.test.create_index, "x",
+ partialFilterExpression={"$and": 5})
+ self.assertRaises(OperationFailure, db.test.create_index, "x",
+ partialFilterExpression={
+ "$and": [{"$and": [{"x": {"$lt": 2}},
+ {"x": {"$gt": 0}}]},
+ {"x": {"$exists": True}}]})
+
+ self.assertEqual("x_1", db.test.create_index(
+ [('x', ASCENDING)], partialFilterExpression={"a": {"$lte": 1.5}}))
+ db.test.insert_one({"x": 5, "a": 2})
+ db.test.insert_one({"x": 6, "a": 1})
+
+ # Operations that use the partial index.
+ explain = db.test.find(
+ {"x": 6, "a": 1}).explain()['queryPlanner']['winningPlan']
+ self.assertEqual("x_1", explain.get('inputStage', {}).get('indexName'))
+ self.assertTrue(explain.get('inputStage', {}).get('isPartial'))
+ explain = db.test.find(
+ {"x": {"$gt": 1}, "a": 1}).explain()['queryPlanner']['winningPlan']
+ self.assertEqual("x_1", explain.get('inputStage', {}).get('indexName'))
+ self.assertTrue(explain.get('inputStage', {}).get('isPartial'))
+ explain = db.test.find(
+ {"x": 6,
+ "a": {"$lte": 1}}).explain()['queryPlanner']['winningPlan']
+ self.assertEqual("x_1", explain.get('inputStage', {}).get('indexName'))
+ self.assertTrue(explain.get('inputStage', {}).get('isPartial'))
+
+ # Operations that do not use the partial index.
+ explain = db.test.find(
+ {"x": 6,
+ "a": {"$lte": 1.6}}).explain()['queryPlanner']['winningPlan']
+ self.assertEqual("COLLSCAN", explain.get('stage'))
+ explain = db.test.find(
+ {"x": 6}).explain()['queryPlanner']['winningPlan']
+ self.assertEqual("COLLSCAN", explain.get('stage'))
+
+ # Test drop_indexes.
+ db.test.drop_index("x_1")
+ explain = db.test.find(
+ {"x": 6, "a": 1}).explain()['queryPlanner']['winningPlan']
+ self.assertEqual("COLLSCAN", explain.get('stage'))
+
  def test_field_selection(self):
  db = self.db
  db.drop_collection("test")