SQL计数器和返回器，双打的结果 [英] SQL Counter and returner, doubles the result

问题描述

我试图做一个列表，显示在我的论坛我的所有类别的。显示该类别名称，一个ID，藏汉作为计数，计数多少线程连接到这一类。

它完美，但是，它打印两次结果

这是SQL

  SELECT categories.category_name，线程.thread_category_id，COUNT（*）
从线程
 INNER JOIN类别ON categories.category_id = threads.thread_category_id 
 GROUP BY categories.category_name经纬，threads.thread_category_id 
  

下面是结果

和，你可以看到，它打印同样的事情两次，它should't。

编辑：这里是ASP

 < ASP：直放站ID =类别=服务器> 
<&HeaderTemplate中GT; 
<表ID =kategorierCELLSPACING =0> 
< TR> 
< TD类=头>名称和LT; / TD> 
< TD类=头的风格=宽度：70像素>&线程LT的数目; / TD> 
< / TR> 
< / HeaderTemplate中> 
<&ItemTemplate中GT; 
< TR> 
将; TD类=项>&下; A HREF =Kategori.aspx的id =&下;％＃评估和演示（thread_category_id）％>中与GT;&下;％＃评估和演示（CATEGORY_NAME ）％> -  ID：<％＃的eval（thread_category_id）％>< / A>< / TD> 
< TD类=项的风格=文本对齐：右><％＃的eval（经纬）％>< / TD> 
< / TR> 
< / ItemTemplate中> 
< FooterTemplate> 
< /表> 
< / FooterTemplate> 
< / ASP：直放站> 
  

解决方案

基本上，你有2个地方，如果你的ASP重复行是正确的：

1），SQL是错误的（也许你就必须使用DISTINCT运算符）

2）C＃编码是错误的（也许你要检查你的数据源）

检查您的SQL请。并与我们分享您的C＃代码。

使用此

  SELECT不同CATEGORY_NAME，thread_category_id，THREADCOUNT 
起价
（SELECT categories.category_name，threads.thread_category_id，COUNT（*）
从线程$ b $'经纬'b INNER JOIN类别ON categories.category_id = threads.thread_category_id 
 GROUP BY categories.category_name，threads.thread_category_id）在
  

I'm trying to make a list, showing all of my Categories on my Forum. Showing the Category name, with an ID, aswell as a count, counting how many Threads is attached to this Category.

It works perfectly, however, it prints the results twice.

This is the SQL

SELECT categories.category_name, threads.thread_category_id, COUNT(*) 
                        AS 'threadCount' FROM threads 
                        INNER JOIN categories ON categories.category_id = threads.thread_category_id
                        GROUP BY categories.category_name, threads.thread_category_id

Here is the result

And as you can see, it prints the same thing twice, which it should't.

EDIT: Here is the ASP.

<asp:Repeater ID="categories" runat="server">
    <HeaderTemplate>
    <table id="kategorier" cellspacing="0">
        <tr>
            <td class="head">Name</td>
            <td class="head" style="width:70px">Number of Threads</td>
        </tr>
    </HeaderTemplate>
    <ItemTemplate>
        <tr>
            <td class="item"><a href="Kategori.aspx?id=<%# Eval("thread_category_id") %>"><%# Eval("category_name") %> - ID: <%# Eval("thread_category_id")%></a></td>
            <td class="item" style="text-align:right"><%# Eval("threadCount") %></td>
        </tr>
    </ItemTemplate>
    <FooterTemplate>
    </table>
    </FooterTemplate>
</asp:Repeater>

解决方案

Basically you have 2 places to duplicate rows if your ASP is correct:

1) SQL is wrong (Probably you have to use DISTINCT operator)

2) C# code is wrong (Probably you have to check your data source)

Check your SQL pls. And share your C# code with us.

Use this

SELECT distinct  category_name, thread_category_id, threadCount
FROM
( SELECT categories.category_name, threads.thread_category_id, COUNT(*) 
                        AS 'threadCount' FROM threads 
                        INNER JOIN categories ON categories.category_id = threads.thread_category_id
                        GROUP BY categories.category_name, threads.thread_category_id ) A

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