mysql 字段排序,该如何处理
mysql 字段排序
在一个sql语句中如果如果需要排序的字段是空的，怎样处理啊，如果想把它排在后面怎么弄啊?
------解决方案--------------------
如果要排序的字段是空，默认会把为空的排在前面。加一个DESC关键词就可倒序排列，也就是空的在最后面
------解决方案--------------------
建议你贴出：
create table.......
insert into table.......
以及期望结果。
------解决方案--------------------
ORDER by isnull(`要按值排序的字段`)
就可以把为空的排在后面，你是这个意思吧？
------解决方案--------------------
(... WHERE 字段名字 IS NOT NULL GROUP BY 字段名字 )
UNION ( ... WHERE 字段名字 IS NULL )
……
------解决方案--------------------
... order by 排序字段='' or 排序字段 id null, 排序字段
------解决方案--------------------
为什么字段为空啊，建表时就应该尽量为非空。
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