如何在where条件下更新多行

Question

我有以下 table 数据我想使用默认数量 =1 更新行，但 ChildItemID 列上的最大（序列）组除外。我也在下面写了查询。

 UPDATE #tempBOM1 SET Quantity=1
    WHERE [Sequence] < (SELECT MAX([Sequence]) FROM #tempBOM1 GROUP BY ChildItemID) and ChildItemID is not null;

with cte as (
    select 
        t.*, 
        max(sequence) over(partition by childItemID) max_sequence
    from mytable t
)
update cte 
set quantity = 1
where sequence <> max_sequence

SELECT * FROM cte

Answer 1

您可以使用 window 函数和可更新的 CTE：

with cte as (
    select 
        t.*, 
        max(sequence) over(partition by childItemID) max_sequence
    from mytable t
)
update cte 
set quantity = 1
where sequence <> max_sequence

如何在where条件下更新多行

How to update multiple rows on where condition

sql

sql-server

sql-server-2008