MySQL查询根据一个公共值对两个表中的一列求和并对另一列进行计数？

我在试图构建一个查询时遇到了一些问题。我希望这里能有点帮助

我有两张桌子。每个表有两列。其描述如下：

表：“代币”

表：“得分”

我需要一个查询，该查询将列出每个名称一次，并使用每个名称列出该名称的点数总和，以及where Color=“RED”的计数

表1的样本数据：

"BOB","GREEN"
"LARRY","RED"
"JIM","BLUE"
"JIM","RED"
"FRANK","RED"
"BOB","BLUE"
"JIM","RED"

表2的样本数据：

"LARRY",100
"BOB",40
"JIM",200
"BOB",100
"PAUL",250

我的表输出类似于（行顺序不重要）：

---

我如何才能做到这一点？

您可以聚合，然后加入：

select t1.name, t1.reds, t2.points
from (select name, sum(color = 'RED') reds from table1 group by name) t1
inner join (select name, sum(points) points from table2 group by name) t2 
    on t1.name = t2.name

如果任一表中缺少

name

s，则可以使用

union all

：

select name, sum(reds) reds, sum(points) points
from 
    select name, 1 reds, 0 points from table1 where color = 'RED'
    union all
    select name, 0, points points from table2
) t 
group by name

BOB,140,0
LARRY,100,1
JIM,200,2
FRANK,0,1
PAUL,250,0

select t1.name, t1.reds, t2.points
from (select name, sum(color = 'RED') reds from table1 group by name) t1
inner join (select name, sum(points) points from table2 group by name) t2 
    on t1.name = t2.name

select name, sum(reds) reds, sum(points) points
from 
    select name, 1 reds, 0 points from table1 where color = 'RED'
    union all
    select name, 0, points points from table2
) t 
group by name