分层错误

Question

这是我的代码：

    with t(branch_id, branch_code, branch, parent_branch_id, level) as
  (
    Select parent_b.BRANCH_ID, parent_b.BRANCH_CODE,
           parent_b.BRANCH, parent_b.PARENT_BRANCH_ID, 0 as level
    from table parent_b
    Where parent_b.branch_Id is null--= 1
    UNION ALL
    Select child_b.BRANCH_ID, child_b.BRANCH_CODE,
           child_b.BRANCH, child_b.PARENT_BRANCH_ID, (t.level+1)
    from table child_b 
    INNER JOIN t parent
       ON parent.branch_id = child_b.parent_branch_id
  )
  select * from t

我的输出错误。哪个错误，我无法找到。

错误：

  

多部分标识符＆＃34; t.level＆＃34;无法受约束。

Answer 1

将t.level更改为parent.level。您已将CTE的别名指定为“parent”。你需要使用它。

  with t(branch_id, branch_code, branch, parent_branch_id, level) as
  (
    Select parent_b.BRANCH_ID, parent_b.BRANCH_CODE,
           parent_b.BRANCH, parent_b.PARENT_BRANCH_ID, 0 as level
    from table parent_b
    Where parent_b.branch_Id is null--= 1
    UNION ALL
    Select child_b.BRANCH_ID, child_b.BRANCH_CODE,
           child_b.BRANCH, child_b.PARENT_BRANCH_ID, (parent.level+1)
    from table child_b 
    INNER JOIN t parent
       ON parent.branch_id = child_b.parent_branch_id
  )
  select * from t