Question

OrderID, OrderTime, OrderItem

1,       1 am,      Orange
1,       2 am,      Apple
2,       3 am,      Grape
3,       2 am,      Apple
3,       3 am,      Coconut
1,       5 am,      Banana
1,       6 am,      Apple

以上是原始表格。以下是我想要的表格。如果订单ID连续相同，我想将订单时间更改为最短时间。

OrderID, OrderTime, OrderItem

1,       1 am,      Orange
1,       1 am,      Apple
2,       3 am,      Grape
3,       2 am,      Apple
3,       2 am,      Coconut
1,       5 am,      Banana
1,       5 am,      Apple

Answer 1

如果您没有指定订单，那么SQL Server中的数据没有“自然”顺序，那么您无法保证返回的订单。您需要一个可用于定义order by的列。一旦你有了这个，你可以做类似的事情

declare @data table 
(
OrderItemId int identity(1,1) primary key,
OrderID int, 
OrderTime datetime, 
OrderItem varchar(10))

insert into @data
SELECT 1,'00:01:00','Orange' UNION ALL
SELECT 1,'00:01:00','Apple' UNION ALL
SELECT 2,'00:03:00','Grape' UNION ALL
SELECT 3,'00:02:00','Apple' UNION ALL
SELECT 3,'00:02:00','Coconut' UNION ALL
SELECT 1,'00:05:00','Banana' UNION ALL
SELECT 1,'00:05:00','Apple';

WITH cte1 AS
(
SELECT *, ROW_NUMBER() over (ORDER BY OrderItemId)-
ROW_NUMBER() over (PARTITION BY OrderID ORDER BY OrderItemId) AS Grp
FROM @data
), cte2 AS
(
SELECT *, MIN(OrderTime) OVER (PARTITION BY OrderID, Grp) AS MinOrderTime
FROM cte1
)
UPDATE cte2 SET OrderTime = MinOrderTime

SELECT OrderID,convert(varchar, OrderTime, 8) OrderItemId, OrderItem
 FROM @data
 ORDER BY OrderItemId

替换sql表中的值

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