Question

我有以下查询：

select a.user_id, sum(c.amount) as all_assets, 
sum(case when b.class='x' then c.amount end) assets_x, 
sum(case when b.class='y' then c.amount end) assets_y, 
sum(case when b.class='z' and c.amount<=100 then c.amount end) assets_z
from a
join b on a.id=b.id
join c on b.id=c.id
group by a.user_id

按用户ID对资产进行分组，并将总资产分为x，y和z类，其中类z和仅z排除c.amount >100的主语。

我的问题是，在计算all_assets时，如何从总数中移除c.amount>100 b.class='z'的主菜？

Answer 1

如果要对select的所有部分执行此操作，请使用where子句：

select a.user_id, sum(c.amount) as all_assets, 
       sum(case when b.class = 'x' then c.amount end) as assets_x, 
       sum(case when b.class = 'y' then c.amount end) as assets_y, 
       sum(case when b.class = 'z' and c.amount <= 100 then c.amount end) as assets_z
from a join
     b
     on a.id = b.id join
     c
     on b.id = c.id
where not (b.class = 'z' and c.amount > 100)
group by a.user_id;

您还可以将此短语称为另一个条件聚合：

select a.user_id,  
       sum(case when b.class in ('x', 'y') or c.amount <= 100 then c.amount end) as all_assets,
       sum(case when b.class = 'x' then c.amount end) as assets_x, 
       sum(case when b.class = 'y' then c.amount end) as assets_y, 
       sum(case when b.class = 'z' and c.amount <= 100 then c.amount end) as assets_z
from a join
     b
     on a.id = b.id join
     c
     on b.id = c.id
group by a.user_id;

此版本假设唯一的类是x，y和z。

从某些条件中删除总值，但不删除其他条件

1 个答案: