docs: private boolean tablesExists() throws SQLException {
          PreparedStatement ps = null;
          try {
              ps = conn.get().prepareStatement(getTablesExistSQL());
              ResultSet results = ps.executeQuery();
              results.close();
              return true;
          } catch (SQLException ex) {
              return false;
          } finally {
              if(ps != null && !ps.isClosed()) {
                  ps.close();
              }
          }
      }