MySQL按分组计数多列

Question

我想计算group by子句中使用的每个不同的组。我使用这个查询现在：

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

这使我产生这样的：

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

我想是：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多条记录是如何有

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

其中语言的频率代表了“阿拉伯语”作为其值的行总数;类似的组频率表示包含'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` ;