[英]How to get min and max from 2 tables in SQL
這是一種選擇; 假設您使用 Oracle(關於您使用 Oracle SQL Developer), x
內聯視圖選擇
start_date
屬於該name
的ID
列值最低的name
(即first_value 按名稱順序按 id 分區)end_date
屬於具有該name
的最高ID
列值的name
(即first_value 按名稱順序按 id DESC 分區)SQL> with
2 -- sample data
3 t1 (pid, name) as
4 (select 123, 'xyz' from dual union all
5 select 234, 'pqr' from dual
6 ),
7 t2 (id, name, start_date, end_date) as
8 (select 1, 'xyz', date '2020-01-01', date '2020-07-20' from dual union all
9 select 2, 'xyz', date '2020-02-01', date '2020-05-30' from dual union all
10 select 3, 'xyz', date '2020-06-30', date '2020-07-30' from dual union all
11 --
12 select 1, 'pqr', date '2020-04-30', date '2020-09-30' from dual union all
13 select 2, 'pqr', date '2020-05-30', date '2020-09-30' from dual union all
14 select 3, 'pqr', date '2020-06-30', date '2020-07-01' from dual
15 )
16 select a.pid,
17 x.name,
18 max(x.start_date) start_date,
19 max(x.end_date) end_date
20 from t1 a join
21 (
22 -- start_date: always for the lowest T2.ID value row
23 -- end_date : always for the highest T2.ID value row
24 select b.name,
25 first_value(b.start_date) over (partition by b.name order by b.id ) start_date,
26 first_value(b.end_date) over (partition by b.name order by b.id desc) end_date
27 from t2 b
28 ) x
29 on a.name = x.name
30 group by a.pid,
31 x.name
32 order by a.pid;
PID NAME START_DATE END_DATE
---------- ---- ---------- ----------
123 xyz 01/01/2020 07/30/2020
234 pqr 04/30/2020 07/01/2020
SQL>
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.