PHPSQLParser\builders\GroupByExpressionBuilder::build PHP Method

    public function build(array $parsed)
    {
        if ($parsed['expr_type'] !== ExpressionType::EXPRESSION) {
            return "";
        }
        $sql = "";
        foreach ($parsed['sub_tree'] as $k => $v) {
            $len = strlen($sql);
            $sql .= $this->buildColRef($v);
            $sql .= $this->buildReserved($v);
            if ($len == strlen($sql)) {
                throw new UnableToCreateSQLException('GROUP expression subtree', $k, $v, 'expr_type');
            }
            $sql .= " ";
        }
        $sql = substr($sql, 0, -1);
        return $sql;
    }

 protected function buildGroupByExpression($parsed)
 {
     $builder = new GroupByExpressionBuilder();
     return $builder->build($parsed);
 }