create table AggregationTable(Id int, [Name] varchar(10))
go
insert into AggregationTable
    select 1,'趙' union all
    select 2,'錢' union all
    select 1,'孫' union all
    select 1,'李' union all
    select 2,'周'
go

Create FUNCTION AggregateString
(
    @Id int
)
RETURNS varchar(1024)
AS
BEGIN
    declare @Str varchar(1024)
    set @Str = ''
    select @Str = @Str + [Name] from AggregationTable
    where [Id] = @Id
    return @Str
END
GO

select dbo.AggregateString(Id),Id from AggregationTable
group by Id