Question

我的SQL有问题。我创建了这个查询：

我不知道如何通过一个查询获得该结果。我知道要计算百分比，我必须将计数器中获得的值乘以100并除以整个计数的总和。你能救我吗？

非常感谢。

Answer 1

我认为最简单的方法是使用变量：

SELECT browser, counter, counter / @sum
FROM (SELECT browser, count(*) as counter, (@sum := @sum + count(*))
      FROM analyticsCbVisits v INNER JOIN
           analyticsCbPlatformsBrowsers pb
           ON v.idChatBotTrackOperation = pb.idChatBotTrackOperation INNER JOIN
           analyticsBrowsers b
           ON pb.browser_id = b.id CROSS JOIN
            (SELECT @sum := 0) params
      WHERE b.idChatBotTrackOperation = 33 
      GROUP BY browser
     ) x

在其他数据库中，这更简单，因为您可以使用窗口函数。

Answer 2

试试这个：

set @csum := 0;
SELECT browser,counter,CONCAT(FORMAT(IF(total=0,0,(counter*100.0)/total),2),'%')  as  percentage FROM(
SELECT  browser, count(*) as counter,@csum := @csum+count(*) as total
FROM analyticsCbVisits 
INNER JOIN analyticsCbPlatformsBrowsers ON analyticsCbVisits.idChatBotTrackOperation = analyticsCbPlatformsBrowsers.idChatBotTrackOperation
INNER JOIN analyticsBrowsers ON analyticsCbPlatformsBrowsers.browser_id = analyticsBrowsers.id
WHERE analyticsCbVisits.idChatBotTrackOperation = 33
GROUP BY browser) t

另一种解决方法：

SELECT browser,counter,CONCAT(FORMAT(IF(total=0,0,(counter*100.0)/total),2),'%')  as  percentage FROM(
    SELECT  browser, count(*) as counter,(SELECT  count(*)
    FROM analyticsCbVisits 
    INNER JOIN analyticsCbPlatformsBrowsers ON analyticsCbVisits.idChatBotTrackOperation = analyticsCbPlatformsBrowsers.idChatBotTrackOperation
    INNER JOIN analyticsBrowsers ON analyticsCbPlatformsBrowsers.browser_id = analyticsBrowsers.id
    WHERE analyticsCbVisits.idChatBotTrackOperation = 33) as total
    FROM analyticsCbVisits 
    INNER JOIN analyticsCbPlatformsBrowsers ON analyticsCbVisits.idChatBotTrackOperation = analyticsCbPlatformsBrowsers.idChatBotTrackOperation
    INNER JOIN analyticsBrowsers ON analyticsCbPlatformsBrowsers.browser_id = analyticsBrowsers.id
    WHERE analyticsCbVisits.idChatBotTrackOperation = 33
    GROUP BY browser) t

Answer 3

SELECT Table1.Browser, Table1.Counter, Round((Table1.Counter/(Select sum(Table1.Counter) from Table1))*100,2) & " %" AS Percentage
FROM Table1;

此查询在Access中完美运行。它也应该在SQL中。试一试

Answer 4

我会使用WITH ROLLUP来获取总计数

    | Browser | Counter |
    ---------------------
    | Firefox |    2    |
    | Chrome  |    1    |
    | NULL    |    3    |

并计算申请方的百分比。

但是 - 如果您只想运行查询并导出结果，可以将总计数保存到子查询中的会话变量中，并在外部选择中使用它：

SELECT browser, counter, 100 * counter / @total as percentage
FROM (
    SELECT browser,
        CASE WHEN browser IS NULL
            THEN @total := COUNT(*)
            ELSE COUNT(*)
        END AS counter
    FROM analyticsCbVisits 
    INNER JOIN analyticsCbPlatformsBrowsers ON analyticsCbVisits.idChatBotTrackOperation = analyticsCbPlatformsBrowsers.idChatBotTrackOperation
    INNER JOIN analyticsBrowsers ON analyticsCbPlatformsBrowsers.browser_id = analyticsBrowsers.id
    WHERE analyticsCbVisits.idChatBotTrackOperation = 33
    GROUP BY browser
) t
WHERE browser IS NOT NULL

以下是简化演示：http://rextester.com/QAT75385

通过查询从组中获取百分比

4 个答案: