此查询生成从1到4的数字。

with recursive z(q) as (
  select 1
  union all
  select q + 1 from z where q < 4
  )
select * from z;

但是，如果我对此进行修改，

with x as (
  select 1 y
  ),
recursive z(q) as (
  select y from x
  union all
  select q + 1 from z where q < 4
  )
select * from z;

它给

错误：“ z”处或附近的语法错误

我在这里做错了什么？