oracle中通过出生日期分组

• 通过sql分组不是太好，通过业务进行分组，就是说通过年龄分组，在代码中在控制
• 通过年龄分组

select count(1) as RYXXBZ,age as XM from(SELECT TRUNC(months_between(sysdate, birthday)/12) AS age from TEST_TABLE) group by age order by count(1) asc

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select case 
    when age between 0 and 1 then '青年' 
    when age between 2 and 5 then '中年' 
    when age>=6 then '老年' end as 年龄段,
count(*) as 人数 
from (SELECT TRUNC(months_between(sysdate, birthday)/12) AS age from TEST_TABLE)
group by case 
     when age between 0 and 1 then '青年' 
    when age between 2 and 5 then '中年' 
    when age>=6 then '老年' 
end;

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