計算紅移余額

Question

DB-小提琴

CREATE TABLE inventory (
    id SERIAL PRIMARY KEY,
    stock_date DATE,
    inbound_quantity INT,
    outbound_quantity INT
);

INSERT INTO inventory
(stock_date, inbound_quantity, outbound_quantity
)
VALUES 
('2020-01-01', '900', '0'),
('2020-01-02', '0', '300'),
('2020-01-03', '400', '250'),
('2020-01-04', '0', '100'),
('2020-01-05', '700', '500');

---

預計 Output ：

庫存日期	入站數量	出站數量	平衡
2020-01-01	900	0	900
2020-01-02	0	300	600
2020-01-03	400	250	750
2020-01-04	0	100	650
2020-01-05	700	500	850

詢問：

SELECT
iv.stock_date AS stock_date,
iv.inbound_quantity AS inbound_quantity,
iv.outbound_quantity AS outbound_quantity,
SUM(iv.inbound_quantity - iv.outbound_quantity) OVER (ORDER BY stock_date ASC) AS Balance
FROM inventory iv
GROUP BY 1,2,3
ORDER BY 1;

---

通過上面的查詢，我能夠計算 PostgresSQL 中的 in bound_quantity和outbound_quantity的余額。
但是，當我在Amazon-Redshift中運行相同的查詢時，出現此錯誤：

Amazon Invalid operation: Aggregate window functions with an ORDER BY clause require a frame clause; 1 條聲明失敗。

我需要如何更改查詢才能使其在 Redshift 中也能正常工作？

Answer 1

正如錯誤所說，您需要添加框架規范子句，即ROWS UNBOUNDED PRECEDING到您的 window function 中。

SELECT iv.stock_date AS stock_date,
       iv.inbound_quantity AS inbound_quantity,
       iv.outbound_quantity AS outbound_quantity,
       SUM(iv.inbound_quantity - iv.outbound_quantity) OVER (
           ORDER BY stock_date ASC 
           ROWS UNBOUNDED PRECEDING
       ) AS Balance
FROM inventory iv
GROUP BY 1,2,3
ORDER BY 1;