Fixed #34060 -- Fixed migrations crash when adding check constraints with JSONField __exact lookup on Oracle.

django/db/backends/oracle/operations.py

@@ -347,9 +347,10 @@ END;
     def lookup_cast(self, lookup_type, internal_type=None):
         if lookup_type in ("iexact", "icontains", "istartswith", "iendswith"):
             return "UPPER(%s)"
-        if (
-            lookup_type != "isnull" and internal_type in ("BinaryField", "TextField")
-        ) or (lookup_type == "exact" and internal_type == "JSONField"):
+        if lookup_type != "isnull" and internal_type in (
+            "BinaryField",
+            "TextField",
+        ):
             return "DBMS_LOB.SUBSTR(%s)"
         return "%s"
 

django/db/backends/postgresql/features.py

@@ -106,6 +106,13 @@ class DatabaseFeatures(BaseDatabaseFeatures):
                     "test_group_by_nested_expression_with_params",
                 }
             )
+        if not is_psycopg3:
+            expected_failures.update(
+                {
+                    "constraints.tests.CheckConstraintTests."
+                    "test_validate_jsonfield_exact",
+                }
+            )
         return expected_failures
 
     @cached_property

django/db/models/fields/json.py

@@ -310,6 +310,11 @@ class JSONExact(lookups.Exact):
             rhs %= tuple(func)
         return rhs, rhs_params
 
+    def as_oracle(self, compiler, connection):
+        lhs, lhs_params = self.process_lhs(compiler, connection)
+        rhs, rhs_params = self.process_rhs(compiler, connection)
+        return f"JSON_EQUAL({lhs}, {rhs})", (*lhs_params, *rhs_params)
+
 
 class JSONIContains(CaseInsensitiveMixin, lookups.IContains):
     pass