RM-95 use Table

records_mover/db/vertica/vertica_db_driver.py

@@ -1,7 +1,7 @@
 from ..driver import DBDriver
 import sqlalchemy
 from sqlalchemy.sql import text
-from records_mover.db.quoting import quote_schema_and_table
+from sqlalchemy import select
 from sqlalchemy.schema import Table, Column
 import logging
 from typing import Optional, Union, Tuple
@@ -47,10 +47,8 @@ def unloader(self) -> Optional[Unloader]:
 
     def has_table(self, schema: str, table: str) -> bool:
         try:
-            sql = ("SELECT 1 "
-                   f"from {quote_schema_and_table(None, schema, table, db_engine=self.db_engine)} "
-                   "limit 0;")
-            self.db_conn.execute(text(sql))
+            table_to_check = Table(table, self.meta, schema=schema)
+            self.db_conn.execute(select(text("1"), table_to_check))
             return True
         except sqlalchemy.exc.ProgrammingError:
             return False

tests/unit/db/vertica/test_vertica_db_driver.py

@@ -54,14 +54,14 @@ def test_schema_sql_but_not_from_export_objects(self):
         self.assertTrue(sql is not None)
 
     def test_has_table_true(self):
-        mock_schema = Mock(name='schema')
-        mock_table = Mock(name='table')
+        mock_schema = 'myschema'
+        mock_table = 'mytable'
         self.assertEqual(True,
                          self.vertica_db_driver.has_table(mock_schema, mock_table))
 
     def test_has_table_false(self):
-        mock_schema = Mock(name='schema')
-        mock_table = Mock(name='table')
+        mock_schema = 'myschema'
+        mock_table = 'mytable'
         self.mock_db_engine.execute.side_effect = sqlalchemy.exc.ProgrammingError('statement', {},
                                                                                   'orig')
         self.assertEqual(False,