SQLite select 内部更新

Question

所以有 2 个 table，Transactions 有 created_at 列，Transaction_associations 有 amount 和 remaining_balance 列，等等.显然，我需要在 amount 列上计算运行 sum(total)，按 created_at 列排序。唯一的问题是，我需要获取在正在计算的当前交易之前创建的所有交易的 SUM。我需要更新查询中的 select 才能 SELECT 和 current_transactions table 才能掌握当前的 created_at 日期。然而我不能。我错过了什么吗？这种方法有替代方法吗？

UPDATE Transaction_associations SET remaining_balance = ( SELECT SUM (Transaction_associations.amount) FROM Transactions JOIN Transaction_associations ON Transactions.id = transaction_id WHERE created_at <= current_transactions.created_at // here ) WHERE id IN ( SELECT id FROM Transaction_associations JOIN Transactions ON Transactions.id = transaction_id WHERE created_at >= '2014-11-24' )

编辑： 添加了示例。

Transactions Transaction_associations created_at amount remaining_balance 2014-02-01 100 100 2014-03-01 50 150 2014-04-01 205 355

后期编辑： 添加了用于 SQLFiddle 的完整代码。我在 SUM 上用 TA2 替换了 Transaction_associations，因为它抱怨 misuse of aggregate: SUM()

DROP TABLE IF EXISTS Transactions; DROP TABLE IF EXISTS Transaction_associations; CREATE TABLE Transactions ( id integer, created_at text); CREATE TABLE Transaction_associations ( id integer, amount integer, remaining_balance integer, transaction_id integer); INSERT INTO Transactions VALUES (1,'2015'); INSERT INTO Transactions VALUES (2,'2014'); INSERT INTO Transactions VALUES (3,'2013'); INSERT INTO Transactions VALUES (4,'2012'); INSERT INTO Transactions VALUES (5,'2010'); INSERT INTO Transaction_associations VALUES (6, 100, 0, 1); INSERT INTO Transaction_associations VALUES (7, 20, 0, 2); INSERT INTO Transaction_associations VALUES (8, 3, 0, 3); INSERT INTO Transaction_associations VALUES (9, 40, 0, 4); INSERT INTO Transaction_associations VALUES (10, 500, 0, 5); UPDATE Transaction_associations SET remaining_balance = ( SELECT SUM(TA2.amount) FROM Transactions JOIN Transaction_associations AS TA2 ON Transactions.id = TA2.transaction_id WHERE created_at <= (SELECT created_at FROM Transactions WHERE id = TA2.transaction_id) ) WHERE transaction_id IN ( SELECT id FROM Transactions WHERE created_at >= '2013' ); SELECT * from Transactions join Transaction_associations on Transactions.id = Transaction_associations.transaction_id;

结果是，这是错误的：

1 2015 6 100 663 1 2 2014 7 20 663 2 3 2013 8 3 663 3 4 2012 9 40 0 4 5 2010 10 500 0 5

结果应该是：

1 2015 6 100 663 1 2 2014 7 20 563 2 3 2013 8 3 543 3 4 2012 9 40 0 4 5 2010 10 500 0 5

Answer 1

要多次使用相同的 table 名称，请重命名其中一个。这对于 UPDATE 是不可能的，因此您必须在 SELECT 中执行此操作。要查找相应的时间戳，请使用另一个子查询。再加上一些简化，这就变成了：

UPDATE Transaction_associations
SET remaining_balance =
(
    SELECT SUM(TA2.amount) 
    FROM Transactions 
    JOIN Transaction_associations AS TA2 ON Transactions.id = TA2.transaction_id
    WHERE created_at <= (SELECT created_at
                         FROM Transactions
                         WHERE id = Transaction_associations.transaction_id)
) 
WHERE transaction_id IN
(
    SELECT id
    FROM Transactions
    WHERE created_at >= '2014-11-24'
);

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