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sql如何去除重复数据

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Jun 07, 2016 pm 05:46 PM

distinctfromnbspselect

sql如何去除重复数据,

很多朋友一听就会想到DISTINCT ,那我们来看看distinct的用法吧.

下面来看看语法:

SELECT DISTINCT column_name(s)FROM table_name

下面看个简单的例子:

<pre class="brush:php;toolbar:false">SELECT DISTINCT City FROM Persons

好了下面我们再来看看另一种方法用group by 来做吧,这个想法是从网上来的下面我们来看看下面的sql.

Select *,m_id from tbname group by m_id order by w_support desc

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