diff --git a/zipline/assets/asset_db_migrations.py b/zipline/assets/asset_db_migrations.py
index 82f9d147..2b1431c5 100644
--- a/zipline/assets/asset_db_migrations.py
+++ b/zipline/assets/asset_db_migrations.py
@@ -24,7 +24,7 @@ def downgrade(engine, desired_version):
     """
 
     # Check the version of the db at the engine
-    with engine.connect() as conn:
+    with engine.begin() as conn:
         metadata = sa.MetaData(conn)
         metadata.reflect()
         version_info_table = metadata.tables['version_info']
@@ -100,7 +100,7 @@ def downgrades(src):
         @do(op.setitem(_downgrade_methods, destination))
         @wraps(f)
         def wrapper(op, conn, version_info_table):
-            version_info_table.delete().execute()  # clear the version
+            conn.execute(version_info_table.delete())  # clear the version
             f(op)
             write_version_info(conn, version_info_table, destination)
 
diff --git a/zipline/assets/asset_writer.py b/zipline/assets/asset_writer.py
index 50e9070d..050904ee 100644
--- a/zipline/assets/asset_writer.py
+++ b/zipline/assets/asset_writer.py
@@ -442,9 +442,9 @@ class AssetDBWriter(object):
         --------
         zipline.assets.asset_finder
         """
-        with self.engine.begin() as txn:
+        with self.engine.begin() as conn:
             # Create SQL tables if they do not exist.
-            self.init_db(txn)
+            self.init_db(conn)
 
             # Get the data to add to SQL.
             data = self._load_data(
@@ -457,25 +457,25 @@ class AssetDBWriter(object):
             self._write_df_to_table(
                 futures_exchanges,
                 data.exchanges,
-                txn,
+                conn,
                 chunk_size,
             )
             self._write_df_to_table(
                 futures_root_symbols,
                 data.root_symbols,
-                txn,
+                conn,
                 chunk_size,
             )
             self._write_assets(
                 'future',
                 data.futures,
-                txn,
+                conn,
                 chunk_size,
             )
             self._write_assets(
                 'equity',
                 data.equities,
-                txn,
+                conn,
                 chunk_size,
                 mapping_data=data.equities_mappings,
             )