Question

我有一个有中间名和中间名的人。我正在尝试编写一个函数来检查给定名称中是否包含某些字母。例如＆＃39; oistmiahf＆＃39;将返回史密斯＆＃39;

我试图用案例来表达：

CREATE FUNCTION dbo.ufn_FindNames(@lettersToSearch nvarchar(50))
    RETURNS nvarchar(max)
AS
BEGIN
    DECLARE @firstName nvarchar(50) = (SELECT FirstName FROM Employees),
    @middleName nvarchar(50) = (SELECT MiddleName FROM Employees),
    @ifNoResult nvarchar(50) = 'No result'

    RETURN CASE
        WHEN (@firstName LIKE '%' + @lettersToSearch + '%') THEN @firstName + ' '
        WHEN (@middleName LIKE '%' + @lettersToSearch + '%') THEN @middleName + ' '
        ELSE @ifNoResult
    END
END
GO

在此之后我用＆＃34; EXEC dbo.ufn_FindNames＆＃39; oistmiahf＆＃39; ＆＃34;我收到错误的＆＃34;子查询返回的值超过1。当子查询遵循=，！=，＆lt;，＆lt; =，＆gt;，＆gt; =或子查询用作表达式时，不允许这样做。＆＃34;

如果我尝试使用相同的功能，但是使用IF转换我又有同样的错误。

CREATE FUNCTION dbo.ufn_FindNames(@lettersToSearch nvarchar(50))
    RETURNS nvarchar(50)
AS
BEGIN
    DECLARE @firstName nvarchar(50) = (SELECT FirstName FROM Employees), 
    @middleName nvarchar(50) = (SELECT MiddleName FROM Employees),
    @result nvarchar(50)

    IF(@firstName LIKE '%' + @lettersToSearch + '%')
    BEGIN
        RETURN @firstName + ' '
    END


    IF(@middleName LIKE '%' + @lettersToSearch + '%')
    BEGIN
        RETURN @middleName + ' '
    END

    RETURN @result
END
GO

SQL使用case或if in function

0 个答案: