SQL根据身份证统计年龄段

 Select sex,
 Sum(Case When 年龄 <=20 Then 1 Else 0 End) As '[0-20岁(人)]',
 Sum(Case When 年龄 Between 21 And 40 Then 1 Else 0 End) As '[21-40岁(人)]',
 Sum(Case When 年龄 Between 41 And 59 Then 1 Else 0 End) As '[41-59岁(人)]',
 Sum(Case When 年龄 Between 60 And 69 Then 1 Else 0 End) As '[60-69岁(人)]' ,
 Sum(Case When 年龄 Between 70 And 79 Then 1 Else 0 End) As '[70-79岁(人)]' ,
 Sum(Case When 年龄 Between 80 And 89 Then 1 Else 0 End) As '[80-89岁(人)]' ,
 Sum(Case When 年龄 >=90 Then 1 Else 0 End) As '[90岁以上(人)]'  
 From
 (
 select  *,FLOOR(DATEDIFF(DATE_FORMAT(now(),'%Y%m%d'),substring(identity,7,8))/365.25)  AS '年龄'  from user 
 ) s 
 WHERE sex!=''
 GROUP BY sex