Avoid expensive select_star on dashboard bootstrap data

superset/connectors/sqla/models.py

@@ -371,7 +371,10 @@ def time_column_grains(self):
 
     @property
     def select_star(self):
-        return self.database.select_star(self.name, show_cols=True)
+        # show_cols and latest_partition set to false to avoid
+        # the expensive cost of inspecting the DB
+        return self.database.select_star(
+            self.name, show_cols=False, latest_partition=False)
 
     def get_col(self, col_name):
         columns = self.columns

superset/data/__init__.py

@@ -17,7 +17,7 @@
 import geohash
 import polyline
 
-from superset import app, db, security_manager, utils
+from superset import app, db, utils
 from superset.connectors.connector_registry import ConnectorRegistry
 from superset.connectors.sqla.models import TableColumn
 from superset.models import core as models

superset/models/core.py

@@ -775,7 +775,7 @@ def compile_sqla_query(self, qry, schema=None):
 
     def select_star(
             self, table_name, schema=None, limit=100, show_cols=False,
-            indent=True, latest_partition=True, cols=None):
+            indent=True, latest_partition=False, cols=None):
         """Generates a ``select *`` statement in the proper dialect"""
         eng = self.get_sqla_engine(schema=schema)
         return self.db_engine_spec.select_star(