add check to guarantee relations is populated

dbt/adapters/spark/impl.py

@@ -3,7 +3,7 @@
 from dataclasses import dataclass
 from typing import Any, Dict, Iterable, List, Optional, Union, Type, Tuple, Callable, Set
 
-from dbt.adapters.base.relation import InformationSchema, SchemaSearchMap
+from dbt.adapters.base.relation import InformationSchema
 from dbt.adapters.capability import CapabilityDict, CapabilitySupport, Support, Capability
 from dbt.contracts.graph.manifest import Manifest
 
@@ -384,26 +384,11 @@ def get_catalog(
     def get_catalog_by_relations(
         self, manifest: Manifest, relations: Set[BaseRelation]
     ) -> Tuple[agate.Table, List[Exception]]:
-        schema_map = SchemaSearchMap()
-        for relation in relations:
-            schema_map.add(relation)
-
-        with executor(self.config) as tpe:
-            futures: List[Future[agate.Table]] = []
-            for info, schemas in schema_map.items():
-                for schema in schemas:
-                    futures.append(
-                        tpe.submit_connected(
-                            self,
-                            schema,
-                            self._get_one_catalog_by_relations,
-                            info,
-                            [schema],
-                            manifest,
-                        )
-                    )
-            catalogs, exceptions = catch_as_completed(futures)
-        return catalogs, exceptions
+        if len(relations) == 0:
+            raise dbt.exceptions.CompilationError(
+                f"Expected non-empty set of relations, found " f"{relations}"
+            )
+        return self.get_catalog(manifest)
 
     def _get_one_catalog(
         self,