SQL - 拍卖 - 列出多个最高出价

Question

我的拍卖

CREATE TABLE Auction (
  id SERIAL PRIMARY KEY,
  owner_id INTEGER REFERENCES Registered(user_id),
  title VARCHAR(50) NOT NULL,
  starting_bid NUMERIC(10,2) NOT NULL CHECK (starting_bid >= 0),
  starting_time TIMESTAMP NOT NULL,
  ending_time TIMESTAMP NULL CHECK (starting_time < ending_time),
  status_id INTEGER REFERENCES AuctionStatus(id),
  winner_id INTEGER REFERENCES Registered(user_id) NULL,
  highest_bid NUMERIC(10,2) NOT NULL
);

我的出价

CREATE TABLE Bid (
  id SERIAL PRIMARY KEY,
  user_id INTEGER REFERENCES Registered(user_id),
  auction_id INTEGER REFERENCES Auction(id),
  bid_value NUMERIC(10,2) CHECK (VALUE > 0),
  creation_date TIMESTAMP NOT NULL,
  valid BOOLEAN DEFAULT TRUE NOT NULL
);

我希望用户能够列出他出价的所有拍卖 + 他在每次拍卖中的最高出价。

我从

开始

SELECT auction.id, auction.title, auction.highest_bid, bid.bid_value
FROM auction
JOIN bid
ON auction.id = bid.auction_id
WHERE bid.owner_id = :userID AND bid.active = TRUE AND auction.status_id = 1

列出他的所有出价，但我无法从这里继续前进以获取用户对每次拍卖的最高出价。

Answer 1

SELECT distinct on (auction.id) auction.id, auction.title, auction.highest_bid, bid.bid_value
FROM auction
JOIN bid
ON auction.id = bid.auction_id
WHERE bid.owner_id = :userID AND bid.active = TRUE AND auction.status_id = 1
ORDER BY auction.id, bid.bid_value desc;

有关详细信息，请参阅：

Select first row in each GROUP BY group?

和

"DISTINCT Clause" 段落来自 http://www.postgresql.org/docs/current/static/sql-select.html

SQL - 拍卖 - 列出多个最高出价

SQL - Auctions - List multiple highest bids

database

postgresql

greatest-n-per-group