摘要: 第一种写法: ifnull(exper1,exper2)判断exper1是否为空,是则用exper2代替,这种当exper1为空串时还会取exper1 第二种写法: (CASE WHEN contractName='' or contractName is null then projectName 阅读全文
posted @ 2021-07-12 18:11 杨吃羊 阅读(1222) 评论(0) 推荐(0)