Use is_relational check for schema caching (#3716) (#3809)

* Use is_relational check for schema caching

* Fix flake8

* Update changelog

CHANGELOG.md

@@ -1,5 +1,8 @@
 ## dbt 0.20.2 (Release TBD)
 
+### Fixes
+- Avoid caching schemas for tests when `store_failures` is not enabled ([#3715](https://github.com/dbt-labs/dbt/issues/3715), [#3716](https://github.com/dbt-labs/dbt/pull/3716))
+
 ### Under the hood
 - Get more information on partial parsing version mismatches ([#3757](https://github.com/dbt-labs/dbt/issues/3757), [#3758](https://github.com/dbt-labs/dbt/pull/3758))
 - Use GitHub Actions for CI ([#3688](https://github.com/dbt-labs/dbt/issues/3688), [#3669](https://github.com/dbt-labs/dbt/pull/3669))

core/dbt/adapters/base/impl.py

@@ -31,7 +31,6 @@
 from dbt.contracts.graph.manifest import Manifest, MacroManifest
 from dbt.contracts.graph.parsed import ParsedSeedNode
 from dbt.exceptions import warn_or_error
-from dbt.node_types import NodeType
 from dbt.logger import GLOBAL_LOGGER as logger
 from dbt.utils import filter_null_values, executor
 
@@ -310,8 +309,7 @@ def _get_cache_schemas(self, manifest: Manifest) -> Set[BaseRelation]:
             self.Relation.create_from(self.config, node).without_identifier()
             for node in manifest.nodes.values()
             if (
-                node.resource_type in NodeType.executable() and
-                not node.is_ephemeral_model
+                node.is_relational and not node.is_ephemeral_model
             )
         }