php-MySql调查不同查询

大佬教程收集整理的这篇文章主要介绍了php-MySql调查不同查询，大佬教程大佬觉得挺不错的，现在分享给大家，也给大家做个参考。

大家好,我确实在MySql查询中苦苦挣扎,我有一个名为“ info”的表,并且其中有一个名为“ rating”的列,评分在1-10之间.

现在,我需要生成一个百分比值,该百分比值表示1-6、7-8和9-10中有多少评级,但我需要它们拼命显示,之后我需要第二个查询,该查询可以从中减去结果的百分比值1-6和9-10.

下面的查询与我从所有研究中获得的查询一样接近,但是我不知道如何仅获得1-6的百分比,而不是全部,以及如何获得第二个查询以减去1-6和9-10个评分百分比.

@H_616_8@SELECT rating, 
   COUNT(*) AS Count, 
   (COUNT(*) / _@R_624_10586@l ) * 100 AS Percentege 
FROM info, 
   (SELECT COUNT(*) AS _@R_624_10586@l FROM info) AS my@R_624_10586@l 
GROUP BY rating

解决方法:

@H_616_8@SELEct if(rating between 1 and 6, '1-6', 
          if( rating between 7 and 8, '7-8',
              '9-10' )
          ) as rating_range,
          count(1) as num
from info 
group by rating_range

Working fiddle

编辑：添加舍入和计算
可以用作子查询.给定分组依据,您需要单独获取总金额：

@H_616_8@SELEct Q.rating_range, 
       Q.num,
       round(Q.num * 100 / Q.@R_624_10586@l, 2) as percent
from (
    SELEct  R.*, 
        (SELEct count(1) from info) as @R_624_10586@l
    from (
        SELECT if(rating between 1 and 6, '1-6', 
                  if( rating between 7 and 8, '7-8',
                      '9-10' )
                  ) as rating_range,
                  count(1) as num
        from info 
        group by rating_range ) R
    ) Q
group by Q.rating_range

就相对价值而言,如果我有一个,我可能会在外部应用程序中做到这一点.否则,您可以执行我想进行的特定查询：

@H_616_8@SELEct Q.rating_range, 
       Q.num,
       round(Q.num * 100 / Q.@R_624_10586@l, 2) as percent,      
       round( (Q.num - Q.@R_624_10586@l_nine_ten) * 100 / Q.@R_624_10586@l, 2) as diff_from_nine_ten      
from (
    SELEct  R.*, 
        (SELEct count(1) from info) as @R_624_10586@l,
        (SELEct count(1) from info where rating > 8 ) as @R_624_10586@l_nine_ten
    from (
        SELECT if(rating between 1 and 6, '1-6', 
                  if( rating between 7 and 8, '7-8',
                      '9-10' )
                  ) as rating_range,
                  count(1) as num
        from info 
        group by rating_range ) R
    ) Q 
group by Q.rating_range

Fiddle for version above

不是很优雅,但是可以用

大佬总结

以上是大佬教程为你收集整理的php-MySql调查不同查询全部内容，希望文章能够帮你解决php-MySql调查不同查询所遇到的程序开发问题。

如果觉得大佬教程网站内容还不错，欢迎将大佬教程推荐给程序员好友。

本图文内容来源于网友网络收集整理提供，作为学习参考使用，版权属于原作者。
如您有任何意见或建议可联系处理。小编QQ：384754419，请注明来意。