[英]PostgreSQL querying through schemas
我想要一個查詢,列出所有狀態為“活動”的客戶。 該查詢將返回被標記為活動客戶的列表。 我的問題是,我在查詢引用其他表的表時迷路了。 這是我的架構。
CREATE TABLE Customer (
ID BIGSERIAL PRIMARY KEY NOT NULL,
fNAME TEXT NOT NULL,
lNAME TEXT NOT NULL,
create_date DATE NOT NULL DEFAULT NOW()
);
CREATE TABLE CustomerStatus (
recordID BIGSERIAL NOT NULL,
ID BIGSERIAL REFERENCES Customer NOT NULL,
status TEXT NOT NULL,
create_date DATE NOT NULL DEFAULT NOW()
);
INSERT INTO Customer (fNAME, lNAME) VALUES ('MARK', 'JOHNSON'), ('ERICK', 'DAWN'), ('MAY', 'ERICKSON'), ('JESS', 'MARTIN');
INSERT INTO CustomerStatus (ID, status) VALUES (1, 'pending'), (1, 'active');
INSERT INTO CustomerStatus (ID, status) VALUES (2, 'pending'), (2, 'active'), (2, 'cancelled');
INSERT INTO CustomerStatus (ID, status) VALUES (3, 'pending'), (3, 'active');
INSERT INTO CustomerStatus (ID, status) VALUES (4, 'pending');
我鼓起勇氣假設record_id是serial =>最新的id將是最后一個產生此qry的ID:
t=# with a as (
select *, max(recordid) over (partition by cs.id)
from Customer c
join CustomerStatus cs on cs.id = c.id
)
select *
from a
where recordid=max and status = 'active';
id | fname | lname | create_date | recordid | id | status | create_date | max
----+-------+----------+-------------+----------+----+--------+-------------+-----
1 | MARK | JOHNSON | 2017-04-27 | 2 | 1 | active | 2017-04-27 | 2
3 | MAY | ERICKSON | 2017-04-27 | 7 | 3 | active | 2017-04-27 | 7
(2 rows)
Time: 0.450 ms
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.