= "SELECT principle.principle_id,principle.description,principle.section_id,COUNT(media.principle_id)as media_count LEFT OUTER JOIN media ON principle.principle_id= media.principl
例如: principle + interest AS principle_plus_interest查询集中的第三列principle_plus_interest给出了一个错误。除了编写50000 + .065*50000 AS principle_plus_interest之外,还有什么方法可以对此进行编码吗?