编写 SQL 函数，但无法按预期工作

Question

奖金		工人
90		1
90		2
50		3
40		4
30		5
20		6
10		7

假设我有一个上面显示的列（它可能以水平顺序列出，抱歉错误）我编写了一个用户定义的函数并想将奖金乘以 3，但我的列中有两个相同的值。 我希望该功能可以检测两个具有相同奖金金额的工人并打印“两名工人具有相同的奖金金额”谁可以帮助摆脱这种情况？

Create function newfunction
(
    @bonus as integer
    , @workers as integer
)
returns varchar(25)
as
begin
    declare @equality as integer 
    declare @returnvalue as varchar(25)

    Select @equality = Bonus
    from Employeestbl
    Where Workers = @workers

    If @equality = @Bonus set @returnvalue = 'there is an error'

    return @returnvalue
end

select *, dbo.newfunction(employeestbl.bonus,employeestbl.workers)
from Employeestbl

Answer 1

我希望该功能可以检测两个具有相同奖金金额的工人并打印“两名工人的奖金金额相同”

这个查询会发现：

IF EXISTS (SELECT Bonus, COUNT(*) FROM Table GROUP BY Bonus HAVING COUNT(*) > 1) PRINT 'two workers have same bonus amount'

想要将奖金乘以 3

UPDATE MyTable SET Bonus = Bonus * 3

假设您不想在两个奖金相同的情况下应用奖金，这里有一个脚本来做到这一点：

IF EXISTS (
    SELECT Bonus, COUNT(*) FROM Table GROUP BY Bonus HAVING COUNT(*) > 1
) 
BEGIN
    PRINT 'two workers have same bonus amount'
END
ELSE
BEGIN
    UPDATE MyTable SET Bonus = Bonus * 3
END

Answer 2

set returnvalue这是一个变量，必须set @returnvalue你在函数中有语法错误。