db_mysqli::execute PHP Method

    public function execute($str)
    {
        $this->initConnect(true);
        if (!$this->_linkID) {
            return false;
        }
        $this->queryStr = $str;
        //释放前次的查询结果
        if ($this->queryID) {
            $this->free();
        }
        //N('db_write',1);
        // 记录开始执行时间
        //G('queryStartTime');
        $result = $this->_linkID->query($str);
        $this->debug();
        if (false === $result) {
            $this->error();
            return false;
        } else {
            $this->numRows = $this->_linkID->affected_rows;
            $this->lastInsID = $this->_linkID->insert_id;
            return $this->numRows;
        }
    }