SQL Server 递归

ALTER FUNCTION  [dbo].[RecursionSysLocation](    
    --Add the parameters for the function here
    @ParentId nvarchar(36)
)
RETURNS TABLE 
AS
RETURN(
    with temp ( [Id], [parentid])
    as(
        selectId, ParentId
        fromSysLocation
        where ParentId = @ParentId
        union all
        selecta.Id, a.ParentId
        fromSysLocation a
        inner join temp on a.ParentId = temp.[Id])
    
    select s.Id, s.ParentId from SysLocation s where Id=@ParentId
    union all
    select * from temp)