mysql函数实现递归查询，函数参数能不能当表名?

Question

mysql函数实现递归查询，函数参数能不能当表名

Answer 1

with a as
(select * from table1 where parentid=0
union all
select b.* from a,table1 b where a.id=b.parentid)
select * from a
用with as 来实现递归