diff --git a/dbt/adapters/default/impl.py b/dbt/adapters/default/impl.py
index 7bae81e3e1f..79327e68be2 100644
--- a/dbt/adapters/default/impl.py
+++ b/dbt/adapters/default/impl.py
@@ -24,6 +24,24 @@
 connections_available = []
 
 
+def _filter_schemas(manifest):
+    """Return a function that takes a row and decides if the row should be
+    included in the catalog output.
+    """
+    schemas = frozenset({
+        node.schema.lower()
+        for node in manifest.nodes.values()
+    })
+
+    def test(row):
+        # the schema may be present but None
+        table_schema = row.get('table_schema')
+        if table_schema is None:
+            return False
+        return table_schema.lower() in schemas
+    return test
+
+
 class DefaultAdapter(object):
     DEFAULT_QUOTE = True
 
@@ -830,10 +848,5 @@ def get_catalog(cls, profile, project_cfg, manifest):
         finally:
             cls.release_connection(profile, GET_CATALOG_OPERATION_NAME)
 
-        schemas = list({
-            node.schema.lower()
-            for node in manifest.nodes.values()
-        })
-
-        results = table.where(lambda r: r['table_schema'].lower() in schemas)
+        results = table.where(_filter_schemas(manifest))
         return results
diff --git a/test/unit/test_postgres_adapter.py b/test/unit/test_postgres_adapter.py
index c5b6d05b39c..c9bf4e694c4 100644
--- a/test/unit/test_postgres_adapter.py
+++ b/test/unit/test_postgres_adapter.py
@@ -7,6 +7,7 @@
 from dbt.adapters.postgres import PostgresAdapter
 from dbt.exceptions import ValidationException
 from dbt.logger import GLOBAL_LOGGER as logger  # noqa
+import agate
 
 
 class TestPostgresAdapter(unittest.TestCase):
@@ -79,3 +80,31 @@ def test_set_zero_keepalive(self, psycopg2):
             port=5432,
             connect_timeout=10)
 
+    @mock.patch.object(PostgresAdapter, 'run_operation')
+    def test_get_catalog_various_schemas(self, mock_run):
+        column_names = ['table_schema', 'table_name']
+        rows = [
+            ('foo', 'bar'),
+            ('FOO', 'baz'),
+            (None, 'bar'),
+            ('quux', 'bar'),
+            ('skip', 'bar')
+        ]
+        mock_run.return_value = agate.Table(rows=rows,
+                                            column_names=column_names)
+
+        # we should accept the lowercase matching 'foo's only.
+        mock_nodes = [
+            mock.MagicMock(spec_set=['schema'], schema='foo')
+            for k in range(2)
+        ]
+        mock_nodes.append(mock.MagicMock(spec_set=['schema'], schema='quux'))
+        nodes = {str(idx): n for idx, n in enumerate(mock_nodes)}
+        # give manifest the dict it wants
+        mock_manifest = mock.MagicMock(spec_set=['nodes'], nodes=nodes)
+
+        catalog = PostgresAdapter.get_catalog({}, {}, mock_manifest)
+        self.assertEqual(
+            set(map(tuple, catalog)),
+            {('foo', 'bar'), ('FOO', 'baz'), ('quux', 'bar')}
+        )