Question

我尝试了这三种不同的方式，而PostgreSQL仍然不喜欢我的状态＆＃34; UPDATE＆＃34;中不允许使用聚合函数。如果不这样做，我不知道如何做到这一点。有人能指出我正确的方向，用我的平均工资来填充我的平均工资领域吗？

尝试1：

UPDATE public."JobCategory"
    SET "AverageWage" = round(avg("Wage"), 4)
FROM public."Employees" WERE "Wage" > 0

尝试2：

UPDATE public."JobCategory" c
INNER JOIN (
  SELECT round(avg("Wage"), 4) as average
  FROM public."Employees"
) x ON c."Index" = x."JobIndex"
SET c."AverageWage" = x.average

尝试3：

UPDATE public."JobCategory" AS v 
SET "AverageWage" = s.round(avg("Wage"), 4)
FROM public."Employees" AS s
WHERE v."Index" = s."JobIndex"

Answer 1

您可以使用子查询执行此操作：

WITH subq AS (
    SELECT round(avg(Wage), 4) as average
    FROM public.Employees
)
UPDATE public.JobCategory jc
SET AverageWage = subq.average
FROM subq

PostgreSQL更新表，其中包含来自另一个表的平均值

1 个答案: