JSONField's __contains lookup doesn't work in nested values on Oracle.

[Mariusz Felisiak]

Oracle doesn't provide a native way for testing containment of JSONField. The current implementation works only for basic examples without supporting nested structures and doesn't follow "the general principle that the contained object must match the containing object as to structure and data contents, possibly after discarding some non-matching array elements or object key/value pairs from the containing object".

It looks that building multi-level/recursive filters with JSON_EXISTS() is the only feasible way, but it's really complicated and can be clunky.

I think we should drop this lookup on Oracle and raise NotSupportedError.

Some examples:

diff --git a/tests/model_fields/test_jsonfield.py b/tests/model_fields/test_jsonfield.py
index 3ce7fc51a9..b659675ec8 100644
--- a/tests/model_fields/test_jsonfield.py
+++ b/tests/model_fields/test_jsonfield.py
@@ -445,8 +445,12 @@ class TestQuerying(TestCase):
         tests = [
             ({}, self.objs[2:5] + self.objs[6:8]),
             ({'baz': {'a': 'b', 'c': 'd'}}, [self.objs[7]]),
+            ({'baz': {'a': 'b'}}, [self.objs[7]]),
+            ({'baz': {'c': 'd'}}, [self.objs[7]]),
             ({'k': True, 'l': False}, [self.objs[6]]),
             ({'d': ['e', {'f': 'g'}]}, [self.objs[4]]),
+            ({'d': ['e']}, [self.objs[4]]),
+            ({'d': [{'f': 'g'}]}, [self.objs[4]]),
             ([1, [2]], [self.objs[5]]),
             ({'n': [None]}, [self.objs[4]]),
             ({'j': None}, [self.objs[4]]),

[Mariusz Felisiak]

​PR

[GitHub <noreply@…>]

In 02447fb1:

Fixed #31835 -- Dropped support for JSONField contains lookup on Oracle.

The current implementation works only for basic examples without
supporting nested structures and doesn't follow "the general principle
that the contained object must match the containing object as to
structure and data contents, possibly after discarding some
non-matching array elements or object key/value pairs from the
containing object".

[Mariusz Felisiak <felisiak.mariusz@…>]

In 028a5f8:

[3.1.x] Fixed #31835 -- Dropped support for JSONField contains lookup on Oracle.

The current implementation works only for basic examples without
supporting nested structures and doesn't follow "the general principle
that the contained object must match the containing object as to
structure and data contents, possibly after discarding some
non-matching array elements or object key/value pairs from the
containing object".
Backport of 02447fb133b53ec7d0ff068cc08f06fdf8817ef7 from master