sql语句中select查询时什么时候加'*'号
逗号？逗号是用于分割字段和表等信息的，逗号分割的是并列的关系
比如要查询几个字段
select
字段1,字段2,字段3……这里用逗号
比如要从几个表里查
……from
表1,表2……
比如一个条件要满足某个范围
where
id
in
(1,2,3,4,5.......)
比如要按几个条件排序
order
by
id
desc,hits
desc...
比如要按几个条件分组
group
by
id,name.....
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绛旓細select * from 琛ㄥ悕 where Convert(varchar(200),fcsj, 111) = '2009/12/12'
