报告有两个独立的专栏

Question

我有3个数据表，我想创建一个报告，向我展示他们的书籍和家具。最大的问题是获得一个包含两列的独立清单：书籍和家具。

create table people (id int primary key)
create table books (id int primary key
   , personId int foreign key references people(id))
create table furnitures (id int primary key
   , personId int foreign key references people(id))
go

insert into people(id)
values (1),(2),(3)
insert into books(id,personId)
values (1,1),(2,1),(3,1),(4,1),(5,1),(6,3),(7,3)
insert into furnitures(id,personId)
values (1,2),(2,2),(3,2),(4,3),(5,3),(6,3),(7,3),(8,3)

我想以这种形式收到报告：

Answer 1

你需要做一个join，但你没有钥匙。所以，让我们使用row_number()创建一个。其余的只是full outer join来组合数据：

select coalesce(b.personId, f.personId) as personId, b.id as bookid, f.id as furnitureid
from (select b.*, row_number() over (partition by personId order by id) as seqnum
      from books b
     ) b
     full join
     (select f.*, row_number() over (partition by personId order by id) as seqnum
      from furnitures f
     ) f
     on f.personId = b.personId and b.seqnum = f.seqnum;