Cake\Database\Query::connection PHP Метод

    public function connection($connection = null)
    {
        if ($connection === null) {
            return $this->_connection;
        }
        $this->_dirty();
        $this->_connection = $connection;
        return $this;
    }

 /**
  * Transforms an insert query that is meant to insert multiple rows at a time,
  * otherwise it leaves the query untouched.
  *
  * The way Firebird works with multi insert is by having multiple select statements
  * joined with UNION.
  *
  * @param \Cake\Database\Query $query The query to translate
  * @return \Cake\Database\Query
  */
 protected function _insertQueryTranslator($query)
 {
     $v = $query->clause('values');
     if (count($v->values()) === 1 || $v->query()) {
         return $query;
     }
     $newQuery = $query->connection()->newQuery();
     $cols = $v->columns();
     $placeholder = 0;
     $replaceQuery = false;
     foreach ($v->values() as $k => $val) {
         $fillLength = count($cols) - count($val);
         if ($fillLength > 0) {
             $val = array_merge($val, array_fill(0, $fillLength, null));
         }
         foreach ($val as $col => $attr) {
             if (!$attr instanceof ExpressionInterface) {
                 $val[$col] = sprintf(':c%d', $placeholder);
                 $placeholder++;
             }
         }
         $select = array_combine($cols, $val);
         if ($k === 0) {
             $replaceQuery = true;
             $newQuery->select($select);
             continue;
         }
         $q = $newQuery->connection()->newQuery();
         $newQuery->unionAll($q->select($select));
     }
     if ($replaceQuery) {
         $v->query($newQuery);
     }
     return $query;
 }