我实际上需要用存档中的下一个可用数据填充不存在的条目。
背景:因此，我有一条记录，其中记录了每个月的每个状态。但是，它仅在有新值时更新，并将旧值保存到上个月。使用MySQL v8。
如何在下一个填写的时间段内使用具有相同ID的数据填写表中的缺失值？
带有archivesDate='2019-08-01'的所有内容都故意在其中包含NULL数据。这意味着下个月是数据开始的时间。
将来需要使用带有identtID的下一个数据填充带有archivesDate='2019-09-01'的中间3个数据；在这种情况下，它来自archivesDate='2019-10-01'。可能是10月，11月或将来的任何时候。它只需要填写下一个值即可。
我尝试过的，但这只是ID上的一个联接，这就是为什么9月显示为NULL的原因。
SELECT
al.statusID,
sa.statusDate,
sa.statusFlagsID,
sa.statusPrice,
al.archivesDate
FROM (
SELECT
sid.statusID AS statusID,
a.archivesID AS archivesID,
a.archivesDate AS archivesDate
FROM (
SELECT
DISTINCT statusID
FROM statusArchive) sid
CROSS JOIN archives a) al
LEFT JOIN statusArchive sa
ON sa.statusID = al.statusID --This needs to be changed to get next value in cases where there is no value available
AND sa.archivesID = al.archivesID --This needs to be changed to get next value in cases where there is no value available
ORDER BY al.archivesDate, al.statusID
当前输出:
statusID statusDate statusFlagsID statusPrice archivesDate
1 2019-08-01
2 2019-08-01
3 2019-08-01
1 2019-09-01
2 2019-09-01
3 2019-09-01
1 2018-10-01 1 37 2019-10-01
2 2018-11-05 1 90 2019-10-01
3 2019-01-01 1 3 2019-10-01
所需的输出:
statusID statusDate statusFlagsID statusPrice archivesDate
1 2019-08-01
2 2019-08-01
3 2019-08-01
1 2018-10-01 1 37 2019-09-01
2 2018-11-05 1 90 2019-09-01
3 2019-01-01 1 3 2019-09-01
1 2018-10-01 1 37 2019-10-01
2 2018-11-05 1 90 2019-10-01
3 2019-01-01 1 3 2019-10-01
编辑:添加了模型源表(提供上述所有信息):
源数据
档案
archivesID archivesDate
1 2019-08-01
2 2019-09-01
3 2019-10-01
STATUSARCHIVE(将s替换为以下列名称中的状态，抱歉，格式化问题)
注意:
archivesID=2中缺少条目sArchiveID sID sFlagsID sPrice sDate archivesID
1 1 NULL NULL NULL 1
2 2 NULL NULL NULL 1
3 3 NULL NULL NULL 1
4 1 1 37 2018-10-01 3
5 2 1 90 2018-11-05 3
6 3 1 3 2019-01-01 3
并使用 DB-Fiddle here和SQL创建数据源:
CREATE TEMPORARY TABLE archives (
archivesID INT,
archivesDate DATE
);
INSERT INTO archives (archivesID, archivesDate) VALUES (1, '2019-08-01');
INSERT INTO archives (archivesID, archivesDate) VALUES (2, '2019-09-01');
INSERT INTO archives (archivesID, archivesDate) VALUES (3, '2019-10-01');
CREATE TEMPORARY TABLE statusArchive (
statusArchiveID INT,
statusID INT,
statusFlagsID INT,
statusPrice DECIMAL,
statusDate DATE,
archivesID INT
);
INSERT INTO statusArchive (statusArchiveID, statusID, statusFlagsID, statusPrice, statusDate, archivesID)
VALUES (1, 1, NULL, NULL, NULL, 1);
INSERT INTO statusArchive (statusArchiveID, statusID, statusFlagsID, statusPrice, statusDate, archivesID)
VALUES (2, 2, NULL, NULL, NULL, 1);
INSERT INTO statusArchive (statusArchiveID, statusID, statusFlagsID, statusPrice, statusDate, archivesID)
VALUES (3, 3, NULL, NULL, NULL, 1);
INSERT INTO statusArchive (statusArchiveID, statusID, statusFlagsID, statusPrice, statusDate, archivesID)
VALUES (4, 1, 1, 37, '2018-10-01', 3);
INSERT INTO statusArchive (statusArchiveID, statusID, statusFlagsID, statusPrice, statusDate, archivesID)
VALUES (5, 2, 1, 90, '2018-11-05', 3);
INSERT INTO statusArchive (statusArchiveID, statusID, statusFlagsID, statusPrice, statusDate, archivesID)
VALUES (6, 3, 1, 3, '2019-01-01', 3);
最佳答案
快速解决方案:将您的注释转换为代码。
AND sa.archivesID = al.archivesID -- This needs to be changed to get next value
-- in cases where there is no value available
变成
AND sa.archivesID = (
SELECT MIN(x.archivesID)
FROM statusArchive x
WHERE x.statusID = al.statusID
AND x.archivesID >= al.archivesID
)
完整查询:
SELECT
al.statusID,
sa.statusDate,
sa.statusFlagsID,
sa.statusPrice,
al.archivesDate
FROM (
SELECT
sid.statusID AS statusID,
a.archivesID AS archivesID,
a.archivesDate AS archivesDate
FROM (SELECT DISTINCT statusID FROM statusArchive) sid
CROSS JOIN archives a
) al
LEFT JOIN statusArchive sa
ON sa.statusID = al.statusID
AND sa.archivesID = (
SELECT MIN(x.archivesID)
FROM statusArchive x
WHERE x.statusID = al.statusID
AND x.archivesID >= al.archivesID
)
ORDER BY al.archivesDate, al.statusID
结果:
| statusID | archivesDate | statusDate | statusFlagsID | statusPrice |
| -------- | ------------ | ---------- | ------------- | ----------- |
| 1 | 2019-08-01 | | | |
| 2 | 2019-08-01 | | | |
| 3 | 2019-08-01 | | | |
| 1 | 2019-09-01 | 2018-10-01 | 1 | 37 |
| 2 | 2019-09-01 | 2018-11-05 | 1 | 90 |
| 3 | 2019-09-01 | 2019-01-01 | 1 | 3 |
| 1 | 2019-10-01 | 2018-10-01 | 1 | 37 |
| 2 | 2019-10-01 | 2018-11-05 | 1 | 90 |
| 3 | 2019-10-01 | 2019-01-01 | 1 | 3 |
View on DB Fiddle
注意:您应该在
statusArchive(statusID, archivesID [other columns])上有一个索引。以下(简短的)查询也适用于给定的样本数据:
select
s.statusID,
s.statusDate,
s.statusFlagsID,
s.statusPrice,
a.archivesDate
from archives a
left join statusArchive s
on s.archivesID = (
select min(x.archivesID)
from statusArchive x
where x.archivesID >= a.archivesID
)
order by a.archivesDate, s.statusID;
对于此查询，您应该在
statusArchive(archivesID)上有一个索引。结果:
| statusID | statusDate | statusFlagsID | statusPrice | archivesDate |
| -------- | ---------- | ------------- | ----------- | ------------ |
| 1 | | | | 2019-08-01 |
| 2 | | | | 2019-08-01 |
| 3 | | | | 2019-08-01 |
| 1 | 2018-10-01 | 1 | 37 | 2019-09-01 |
| 2 | 2018-11-05 | 1 | 90 | 2019-09-01 |
| 3 | 2019-01-01 | 1 | 3 | 2019-09-01 |
| 1 | 2018-10-01 | 1 | 37 | 2019-10-01 |
| 2 | 2018-11-05 | 1 | 90 | 2019-10-01 |
| 3 | 2019-01-01 | 1 | 3 | 2019-10-01 |
View on DB Fiddle
但是-我不知道这是否会在任何可能的数据集上返回期望的结果，因为我只能从样本数据和结果中猜测确切的要求。
更新资料
如果需要由相应的
archivesDate排序的下一行，则需要一个ORDER BY ... LIMIT 1子查询:SELECT
al.statusID,
sa.statusDate,
sa.statusFlagsID,
sa.statusPrice,
al.archivesDate
FROM (
SELECT
sid.statusID AS statusID,
a.archivesID AS archivesID,
a.archivesDate AS archivesDate
FROM (SELECT DISTINCT statusID FROM statusArchive) sid
CROSS JOIN archives a
) al
LEFT JOIN statusArchive sa
ON sa.statusID = al.statusID
AND sa.archivesID = (
SELECT x.archivesID
FROM statusArchive x
JOIN archives y ON y.archivesID = x.archivesID
WHERE x.statusID = al.statusID
AND y.archivesDate >= al.archivesDate
ORDER BY y.archivesDate ASC
LIMIT 1
)
ORDER BY al.archivesDate, al.statusID;
确保您有索引
statusArchive(statusID [, other columns])以及x.statusID = al.statusID的SELECT DISTINCT statusID FROM statusArchive条件的archives(archivesID, archivesDate, [, other columns])以及ORDER BY子句y.archivesID = x.archivesID。