SQL需要连接表和返回值的条件

Question

我有两个表需要加入和聚合。

表 1 每个日期和车辆有 1 行 表 2 每个日期和车辆可以有多行

我想加入日期和车辆，并检索大于 table1.max_job_complete_date 的 min(table2.end_times)。所需的值不一定是 table2 的最大 end_times，所以我不能简单地在分区上使用 row_number() ...

simplified visual of the two tables

我尝试了以下方法，但这并不一定会专门为该日期和驱动程序拉最大 end_time。

select
a."date",
a.vehicle,
a.max_job_complete_date,
from table1 as a
left join table2 as b
on b."date" = a."date"
and b.vehicle = a.vehicle
where b.end_times >= (select(max_load_complete_time from table1))

Answer 1

select
a."date",
a.vehicle,
a.max_job_complete_date,
min(b.end_time)
from table1 as a
left join table2 as b
on b."date" = a."date"
and b.vehicle = a.vehicle
Group by
a."date",
a.vehicle,
a.max_job_complete_date
Having b.end_time>a.max_job_complete_date

Answer 2

关联子查询可能是最简单的解决方案：

select a.*,
       (select min(b.date)
        from table2 b
        where b.vehicle = a.vehicle and
              b."date" = a."date" and
              b.end_time >= a.max_load_complete_time
       ) as next_b_date
from table1 a;