"整理" GROUP BY"的&QUOT结果;计数? [英] "Order by" result of "group by" count?
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问题描述
此查询
Message.where("message_type = ?", "incoming").group("sender_number").count
将返回我的哈希值。
will return me an hash.
OrderedHash {"1234"=>21, "2345"=>11, "3456"=>63, "4568"=>100}
现在我想通过各组数订购。我怎样才能做到这一点在查询中。
Now I want to order by count of each group. How can I do that within the query.
推荐答案
要做到这一点,最简单的方法是把一个订单子句添加到原始查询。如果你给计数方法的具体领域,它会生成一个名为count_ {}栏,可以通过添加的顺序调用生成的SQL中使用的输出列:
The easiest way to do this is to just add an order clause to the original query. If you give the count method a specific field, it will generate an output column with the name count_{column}, which can be used in the sql generated by adding an order call:
Message.where('message_type =?','来电')。组(sender_number)。为了(count_id ASC)。COUNT('身份证')
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