code: public function fetchIds($tableName, array $criterias, array $identifiersFields = array('id'), $shardingKey = null, $forceFromMaster = false, array $options = array())
      {
          return $this->fetch($tableName, $criterias, $shardingKey, $identifiersFields, true, $forceFromMaster, $options);
      }
docs: @param string $tableName
  @param array  $criterias
  @param array  $identifiersFields
  @param null   $shardingKey
  @param bool   $forceFromMaster
  @param array  $options
  
  @return array
  @throws \Exception