根据EmployeeVersion列更新CurrentRecord列

Question

我有下表包含每个员工的版本：

EmployeeId Status Department CurrentRecord EmployeeVersion
45         1      33         0             1
45         1      45         0             2
45         2      45         0             3

我想更新CurrentRecord并将其设置为EmployeeVersion最大的记录（因为它是最新版本），将其设置为1，如下所示：

EmployeeId Status Department CurrentRecord EmployeeVersion
45         1      33         0             1
45         1      45         0             2
45         2      45         1             3

这是我的查询：

UPDATE DimEmployeeSharedV1 
  SET CurrentRecord = 1 
WHERE EmployeeVersion = (
  SELECT MAX(e.EmployeeVersion)
  FROM DimEmployeeSharedV1 e
  WHERE e.EmployeeId = EmployeeId
  GROUP BY e.EmployeeId
)

我有以下错误：

子查询返回了多个值。当子查询遵循=，！=，，> =，或当子查询用作表达式。

Answer 1

您可以使用可更新的cte：

with ucte as (
     select v.*, row_number() over (partition by EmployeeId order by EmployeeVersion) as seq
     from DimEmployeeSharedV1 v
)
update ucte 
     set CurrentRecord = 1 
where seq = 1;

相关子查询也将起作用：

UPDATE v1
      SET v1.CurrentRecord = 1 
FROM DimEmployeeSharedV1 v1
WHERE v1.EmployeeVersion = (SELECT MAX(e.EmployeeVersion) 
                            FROM DimEmployeeSharedV1 e
                            WHERE e.EmployeeId = v1.EmployeeId
                           );

Answer 2

Demo on db<>fiddle

; WITH cte as(
 select EmployeeId, max(EmployeeVersion) as EmployeeVersion
 from #A
 group by EmployeeId
)
update a
set CurrentRecord = 1
from #A a
inner join cte on a.EmployeeId = cte.EmployeeId and a.EmployeeVersion = cte.EmployeeVersion

输出