Update to

Author: MartinGotelli

langchain_postgres/vectorstores.py

@@ -66,7 +66,7 @@ class DistanceStrategy(str, enum.Enum):
     "$in",
     "$nin",
     "$between",
-    "$null",
+    "$exists",
 }
 
 TEXT_OPERATORS = {
@@ -710,10 +710,10 @@ def _handle_field_filter(
                 return queried_field.ilike(filter_value)
             else:
                 raise NotImplementedError()
-        elif operator == "$null":
+        elif operator == "$exists":
             if not isinstance(filter_value, bool):
                 raise ValueError(
-                    "Expected a boolean value for $null "
+                    "Expected a boolean value for $exists "
                     f"operator, but got: {filter_value}"
                 )
             condition = func.jsonb_exists(

tests/unit_tests/fixtures/filtering_test_cases.py

@@ -226,19 +226,19 @@
 TYPE_6_FILTERING_TEST_CASES = [
     # These involve the special operator $null
     (
-        {"happiness": {"$null": True}},
+        {"happiness": {"$exists": True}},
         [],
     ),
     (
-        {"happiness": {"$null": False}},
+        {"happiness": {"$exists": False}},
         [1, 2, 3],
     ),
     (
-        {"sadness": {"$null": True}},
+        {"sadness": {"$exists": True}},
         [3],
     ),
     (
-        {"sadness": {"$null": False}},
+        {"sadness": {"$exists": False}},
         [1, 2],
     ),
 ]

tests/unit_tests/test_vectorstore.py

@@ -508,8 +508,8 @@ def test_pgvector_with_with_metadata_filters_6(
         {"$and": {}},
         {"$between": {}},
         {"$eq": {}},
-        {"$null": {}},
-        {"$null": 1},
+        {"$exists": {}},
+        {"$exists": 1},
     ],
 )
 def test_invalid_filters(pgvector: PGVector, invalid_filter: Any) -> None:
@@ -524,6 +524,7 @@ def test_validate_operators() -> None:
         "$and",
         "$between",
         "$eq",
+        "$exists",
         "$gt",
         "$gte",
         "$ilike",
@@ -533,6 +534,5 @@ def test_validate_operators() -> None:
         "$lte",
         "$ne",
         "$nin",
-        "$null",
         "$or",
     ]