SQL 使用先验连接更新查询的语法

SQL syntax for update query with connect by prior

我开始使用 SQL 并面临分层查询。同时,我使用 connect by prior 命令成功 select 行,但未能更新。这是我的更新查询:

update HTABLE set status = 'INACTIVE'
  WHERE STATUS <> 'CLOSE'
  Connect by prior PARENT_ID=ID start with PARENT_ID=12345;

我得到了SQL Error: ORA-00933: SQL command not properly ended。如何分层更新 table?

编辑

我也试过把where条件放在start with里,但是没用:

update HTABLE set status = 'INACTIVE'
  Connect by prior PARENT_ID=ID start with PARENT_ID=12345 AND STATUS <> 'CLOSE';

您可以使用子句 where id in (select ... connect by...) 进行更新,也可以使用 merge:

merge into htable h
using (select distinct id 
         from htable 
         where status <> 'CLOSE'
         connect by prior parent_id = id 
         start with parent_id = 11) src
on (h.id = src.id)
when matched then update set status = 'INACTIVE'

测试数据:

create table htable (id number(4), parent_id number(4), status varchar2(10));
insert into htable values (   1, null, 'ACTIVE');
insert into htable values (  11,    1, 'CLOSE');
insert into htable values (  12,    1, 'ACTIVE');
insert into htable values ( 111,   11, 'ACTIVE');
insert into htable values ( 112,   11, 'ACTIVE');
insert into htable values ( 121,   12, 'ACTIVE');
insert into htable values (   2, null, 'ACTIVE');
insert into htable values (  21,    2, 'ACTIVE');
insert into htable values ( 211,   21, 'ACTIVE');
insert into htable values ( 212,   21, 'ACTIVE');

merge之后:

   ID PARENT_ID STATUS
----- --------- ----------
    1           INACTIVE
   11         1 INACTIVE
   12         1 ACTIVE
  111        11 INACTIVE
  112        11 INACTIVE
  121        12 ACTIVE
    2           ACTIVE
   21         2 ACTIVE
  211        21 ACTIVE
  212        21 ACTIVE

分层查询仅适用于 SELECT。它不适用于 UPDATE(我同意如果可以的话它会很整洁)。

所以你可以做的是:

update HTABLE 
set status = 'INACTIVE'
WHERE STATUS <> 'CLOSE'
and id in ( select c.id
            from htable
            connect by prior ID = PARENT_ID 
            start with PARENT_ID = 12345);

注意列的顺序 connect by prior ID = PARENT_ID。通常我们想从 START WITH 行沿着树向下走,这就是我所做的。您的排序 connect by prior PARENT_ID = ID 从 12345 沿着树向上移动到它的 parents、grandparents 等。如果这是您想要的,请将 connect by 子句切换回来。