我的第一个sql server function

alter function GetDtoScheme(
@dtoOldName varchar(50),
@dtoNewName varchar(50),
@dbName varchar(50))
returns @scheme table
(
    columnName nvarchar(128),
    newColumnName nvarchar(128)
)
as
begin
    insert into @scheme
    select syscolumns.name,replace(syscolumns.name,@dtoOldName,@dtoNewName) FROM syscolumns
    WHERE syscolumns.id = object_id(@dbName+'.dbo.AA_'+@dtoOldName+'_Ext') and syscolumns.name like '%'+@dtoOldName+'%'
    return
end