SQL筛选器基于SQL查询

Question

输入表格 - t1

make   | model | engine | kms_covered  | start   | end
-------------------------------------------------------
suzuki | sx4   | petrol | 11           | City A  | City D
suzuki | sx4   | diesel | 150          | City B  | City C
suzuki | swift | petrol | 140          | City C  | City B
suzuki | swift | diesel | 18           | City D  | City A
toyota | prius | petrol | 16           | City E  | City A
toyota | prius | hybrid | 250          | City B  | City E

需要获取记录的子集，以便start和end只是diesel和hybrid车辆都位于start或end。

在上述情况下，期望只有城市B符合条件并期望输出表格如下

输出表格

make   | model | engine | kms_covered  | start   | end
-------------------------------------------------------
suzuki | sx4   | diesel | 150          | City B  | City C
suzuki | swift | petrol | 140          | City C  | City B
toyota | prius | hybrid | 250          | City B  | City E

两步流程

1. 获取diesel或hybrid
中start和end辆汽车的城市列表
2. 仅使用＃1
中的城市的记录对该表进行子集

如下所示，需要有关起点的帮助。

select * from t1
 where start in () or end in ()

Answer 1

嗯，嗯。 。 。如果我理解了这个问题，您可以使用CTE获取城市列表，然后使用它来解决您的问题：

with c as (
      select city
      from (select start as city, engine
            from t1
            union all
            select end, engine
            from t1
           )
      where engine in ('petrol', 'deisel')
      group by city
      having count(distinct engine) = 2
     )
select t1.*
from t1
where t1.start in (select city from c) and
      t1.end in (select city from c);