code: @Override
      public boolean schemaExists() {
          PreparedStatement ps = null;
          try {
              ps = getPreparedStatement(SIMPLE_SELECT_SQL);
              ps.executeQuery();
              return true;
          } catch (SQLException e) {
              return false;
          } finally {
              if (ps != null) {
                  try {
                      ps.close();
                  } catch (SQLException e) {
                      // Ignore it
                  }
              }
          }
      }
docs: {@inheritDoc}