gate bucketing queries on sqlalchemy version (#6841)

* gate bucketing queries on sqlalchemy version

* add comment

* adjust comment

python_modules/dagster/dagster/core/storage/runs/sql_run_storage.py

@@ -67,6 +67,13 @@ def upgrade(self):
         out-of-date instance of the storage up to date.
         """
 
+    @property
+    def supports_bucket_queries(self):
+        # This is a temporary stopgap until we can either pin SQLAlchemy>=1.4.0 (blocked by airflow
+        # compat issues) or switch the bucketing query to use backwards-compatible syntax (that
+        # avoids calling `.subquery` on a select statement).
+        return db.__version__ >= "1.4.0"
+
     def fetchall(self, query):
         with self.connect() as conn:
             result_proxy = conn.execute(query)

python_modules/dagster/dagster/core/storage/runs/sqlite/sqlite_run_storage.py

@@ -121,7 +121,10 @@ def _alembic_downgrade(self, rev="head"):
 
     @property
     def supports_bucket_queries(self):
-        return get_sqlite_version() > MINIMUM_SQLITE_BUCKET_VERSION
+        return (
+            super().supports_bucket_queries and
+            get_sqlite_version() > MINIMUM_SQLITE_BUCKET_VERSION
+        )
 
     def upgrade(self):
         self._check_for_version_066_migration_and_perform()