获取范围的最小值和最大值

Question

下面的查询会给我的ID列表我需要运行此之后立即执行更新：

SELECT TOP 5 WorkflowEventProcessingID 
FROM Master.WorkflowEventProcessing 
WHERE ProcessingToken IS NULL 
ORDER BY WorkflowEventProcessingId 

有没有办法让分（55034）和最大值（55038）这个范围的ID，在一个select语句，所以我可以做这样的事情：

UPDATE WorkflowEventProcessing 
SET ProcessingToken = <guid here> 
WHERE WorkflowEventProcessingId >= @minId 
    AND WorkflowEventProcessingId <= @maxId 

我想是这样的，但我的路要走：

DECLARE @minId INT 
DECLARE @maxId INT 

SELECT TOP 5 @minId = min(WorkflowEventProcessingID), @maxId = MAX(WorkflowEventProcessingID) 
FROM Master.WorkflowEventProcessing 
WHERE ProcessingToken IS NULL 
ORDER BY WorkflowEventProcessingId 

编辑

我不想因为我得到这个死锁做一个更新与子SELECT。所以我被告知将SELECT和UPDATE分开，给单独的DELETE进程一个在UPDATE和SELECT之间运行的机会。

Answer 1

尝试

DECLARE @min INT 
DECLARE @max INT 

select @min = min(WorkflowEventProcessingID), 
     @max = max(WorkflowEventProcessingID) 
from (
     SELECT TOP 5 WorkflowEventProcessingID 
     FROM Master.WorkflowEventProcessing 
     WHERE ProcessingToken IS NULL 
     ORDER BY WorkflowEventProcessingId 
    ) x 

然后做这样的

UPDATE WorkflowEventProcessing 
SET ProcessingToken = <guid here> 
WHERE WorkflowEventProcessingId between @min and @max 

Answer 2

考虑使用子查询，而不是一个范围：

UPDATE WorkflowEventProcessing 
SET  ProcessingToken = <guid here> 
WHERE WorkflowEventProcessingId in 
     (
     SELECT TOP 5 WorkflowEventProcessingID 
     FROM Master.WorkflowEventProcessing with (updlock, holdlock) 
     WHERE ProcessingToken IS NULL 
     ORDER BY 
       WorkflowEventProcessingId 
     ) 

Answer 3

那岂不是更容易？：

UPDATE WorkflowEventProcessing 
SET ProcessingToken = <guid here> 
WHERE WorkflowEventProcessingId IN (SELECT TOP 5 WorkflowEventProcessingID 
FROM Master.WorkflowEventProcessing 
WHERE ProcessingToken IS NULL 
ORDER BY WorkflowEventProcessingId) 

好了，看到你的评论，你不能在UPDATE使用SELECT（虽然我真的不明白为什么你不能），并假设SQL Server的2005+，你可以尝试以下方法：

;WITH CTE AS 
(
    SELECT TOP 5 WorkflowEventProcessingID 
    FROM Master.WorkflowEventProcessing 
    WHERE ProcessingToken IS NULL 
    ORDER BY WorkflowEventProcessingId 
) 
UPDATE CTE 
SET ProcessingToken = <guid here>