Question

with T1 as 
            (  select tree.* from tree where parent_id = 2
            union all 
            select tree.* from tree 
            join T1 on (tree.parent_id=T1.id) 
            ) 
            select * from T1

此查询选择分层树中的所有子节点。

我需要做的是，从上面的查询中返回的所有结果，都是以1的增量更新名为[level]的字段。

我尝试了一些排列，但是我发现无法更新派生表的错误

Answer 1

; with  T1 as 
        (
        select  tree.* 
        from    tree 
        where   parent_id = 2
        union all 
        select  tree.* 
        from    tree 
        join    T1 
        on      tree.parent_id=T1.id
        ) 
 update tree
 set    level = level + 1
 where  id in
        (
        select  id
        from    t1
        )

请帮我把它变成更新查询

1 个答案: