Question

我想计算group by子句中使用的每个不同的组。我现在正在使用此查询：

SELECT language, group,  count(*) AS frequency
FROM bfs
where firstname <> ''
GROUP BY language, group

这给了我这样的结果：

'Language' 'Group'                'Frequency' 
'ARABIC'   'LEBANESE'               1080 
'ARABIC'   'MUSLIM'                40963 
'ARABIC'   'MUSLIM MIDDLE EAST'      349 
'ARABIC'   'MUSLIM  NORTH AFRICAN'   549

我想要的是：而不是语言和组列的每个组合的总频率，我想知道每种语言和组属性的记录有多少

'Language' 'Group' 'Frequency' 'Language Frequency' 'Group Frequency'
'ARABIC'   'LEBANESE' 1080        42941              1080

其中语言频率表示以'ARABIC'作为其值的总行数;类似地，组频率表示包含“LEBANESE”作为组频率的总行数。任何帮助将不胜感激。

谢谢！

Answer 1

SELECT 
    g.language, g.`group`, g.frequency,
    gl.language_frequency, gg.group_frequency
FROM
      ( SELECT language, `group`,  COUNT(*) AS frequency
        FROM bfs
        WHERE firstname > ''
        GROUP BY language, `group`
      ) AS g
    JOIN
      ( SELECT language, COUNT(*) AS languageFrequency
        FROM bfs
        WHERE firstname > ''
        GROUP BY language
      ) AS gl
      ON gl.language = g.language
    JOIN
      ( SELECT `group`, COUNT(*) AS group_frequency
        FROM bfs
        WHERE firstname > ''
        GROUP BY `group`
      ) AS gg
      ON gg.`group`= g.`group` ;

MySQL在group by子句中计算多个列

1 个答案: