mysql - 创建表的统计信息，以防万一

我有一张桌子，上面有生日和性别

SELECT `tblresultdatetime`, `tblresultbirthdate`, `tblgendertexten`

FROM `ci_wizard_results`

INNER JOIN ci_wizard_genders ON ci_wizard_results.tblresultgender = ci_wizard_genders.tblgenderid

返回：

现在我想创建一个这样的表：

所以我想创建一个表格，指出年龄组等。
我想我首先得把日期转换成年龄：

    select *,year(`tblresultdatetime`)-year(`tblresultbirthdate`) - (right(`tblresultdatetime`,5) < right(`tblresultbirthdate`,5)) as age from `ci_wizard_results`

但在那之后，我不知道如何继续下去。我认为我应该使用案例：

    select *,year(`tblresultdatetime`)-year(`tblresultbirthdate`) - (right(`tblresultdatetime`,5) < right(`tblresultbirthdate`,5)) as age,
count(case when age <= 30 and age> 39 then 1 end) as agegroup3039


from `ci_wizard_results`

但你不能用化名以防万一，所以我有点困了。有什么建议可以继续吗？
（我的最终目标是通过reportico在报表中显示数据）
谢谢！

最佳答案

假设年龄是简单地使用

year(`tblresultdatetime`)-year(`tblresultbirthdate`)

你可以使用case when和group by eg

select
        case when   year(`tblresultdatetime`)-year(`tblresultbirthdate`) between 0 and 30 then '0 - 30'
             when   year(`tblresultdatetime`)-year(`tblresultbirthdate`) between 31 and 40 then '31 - 40'
             when   year(`tblresultdatetime`)-year(`tblresultbirthdate`) between 41 and 50 then '41 - 50'
             when   year(`tblresultdatetime`)-year(`tblresultbirthdate`) between 51 and 60 then '51 - 60'
             when   year(`tblresultdatetime`)-year(`tblresultbirthdate`) between 61 and 70 then '61 - 70'
             else   '70+' as Group end,
        sum(case when  `tblgendertexten`  = 'man'  then 1 else  0 end)  as man,
        sum(case when  `tblgendertexten`  = 'woman'  then 1 else  0 end)  as woman,
        sum(1)  as total
FROM `ci_wizard_results`
INNER JOIN ci_wizard_genders ON ci_wizard_results.tblresultgender = ci_wizard_genders.tblgenderid
group by    case when   year(`tblresultdatetime`)-year(`tblresultbirthdate`) between 0 and 30 then '0 - 30'
             when   year(`tblresultdatetime`)-year(`tblresultbirthdate`) between 31 and 40 then '31 - 40'
             when   year(`tblresultdatetime`)-year(`tblresultbirthdate`) between 41 and 50 then '41 - 50'
             when   year(`tblresultdatetime`)-year(`tblresultbirthdate`) between 51 and 60 then '51 - 60'
             when   year(`tblresultdatetime`)-year(`tblresultbirthdate`) between 61 and 70 then '61 - 70'
             else   '70+' as Group end
union
select
        'total ',
        sum(case when  `tblgendertexten`  = 'man'  then 1 else  0 end)  as man,
        sum(case when  `tblgendertexten`  = 'woman'  then 1 else  0 end)  as woman,
        sum(1)  as total
FROM `ci_wizard_results`
INNER JOIN ci_wizard_genders ON ci_wizard_results.tblresultgender = ci_wizard_genders.tblgenderid

关于mysql - 创建表的统计信息，以防万一，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/40442999/