code: public Iterable<DConnection> queryByProviderUserId(java.lang.String providerUserId) {
      return queryByField(null, DConnectionMapper.Field.PROVIDERUSERID.getFieldName(), providerUserId);
    }
docs: query-by method for field providerUserId
  @param providerUserId the specified attribute
  @return an Iterable of DConnections for the specified providerUserId