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sql查询统计，根据新闻类别ID统计，没有数据显示0

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Release： 2016-06-07 17:40:24
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有两张表，新闻信息表MessageInfo和新闻类别表MessageType。表结构如下： 然后需要实现下面这种查询结果： 这个是我面试时遇到的，上面的新闻类型是乱写的。当时没有做出来，然后回来又研究了下。 刚开始是这么想的，新闻类型表MessageType左连接left join新

有两张表，新闻信息表MessageInfo和新闻类别表MessageType。表结构如下：

然后需要实现下面这种查询结果：

这个是我面试时遇到的，上面的新闻类型是乱写的。当时没有做出来，网站空间，然后回来又研究了下。

刚开始是这么想的，网站空间，新闻类型表MessageType左连接left join新闻信息表MessageInfo，筛除那些新闻ID为空的，然后根据新闻类型名直接分组统计。

,MessageType left join MessageInfo MessageName ，网站空间

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