src/Db/DataReader.php
public function next()
    {
        if ($this->_index === -1) {
            $this->_row = reset($this->_results);
        } else {
            $this->_row = next($this->_results);
        }
        $this->_index++;
    }
public function next()
    {
        if ($this->_index === -1) {
            $this->_row = reset($this->_results);
        } else {
            $this->_row = next($this->_results);
        }
        $this->_index++;
    }
Moves the internal pointer to the next row.
This method is required by the interface [[\Iterator]].