在mysql查询中对数据进行分组或数据透视，使行成为列

Question

我只是遇到了麻烦，无法对我需要的查询进行分类。我有这样

colDist  colGender   attnedancePrcnt 
Place-1  Male     2.5 % 
Place-1  Female    1.5% 
Place-2  Male     3.5% 
Place-2  Female    2.1% 

的情景现在我需要在mysql中查询到有这样

colDist  colMale   colFemale 
Place-1  2.5%    1.5 % 
Place-2  3.5%    2.1 % 

数据这有点组由coldDist但我只是面临的麻烦，使colMale并从第一个数据集colfemale到第二个。

高级谢谢。

这种方法.....

select colDist, if(colGender='Male',colGender,null) as colMale , 
     if(colGender='Female',colGender,null) as colFemale 
from tablename 

给了我这样的

colDist  colMale   colFemale   attnedancePrcnt 
Place-1  Male    NULL     2.5 
Place-1  NULL    Female    1.5 
Place-2  Male    NULL     3.5 
Place-2  NULL    Female    2.1 

的结果，但我又需要他们这样的：

colDist  colMale   colFemale 
Place-1  2.5%    1.5 % 
Place-2  3.5%    2.1 % 

那么怎么可以根据需要对数据进行分组或转储？

谢谢。

Answer 1

SELECT 
    t1.colDist, 
    t1.attnedancePrcnt AS colMale, 
    t2.attnedancePrcnt AS colFemale 
FROM 
    tablename AS t1 
INNER JOIN tablename AS t2 ON t1.colDist = t2.colDist 
AND t1.colGender != t2.colGender 
WHERE 
    t1.colGender = 'Male' 

另外值得一提的是，“attnedance”应拼写“出勤”。

Answer 2

检查是否符合您的要求它的工作原理：

select colDist, if(colGender='Male',colGender,null) as colMale , 
     if(colGender='Female',colGender,null) as colFemale 
from tablename