删除sql或javascript循环中的层次结构行

我正在使用postgresql，我想找到一种递归删除行和属于它的子行的方法。sql或javascript循环
e、 g
如果要删除

TagId:0

，还需要删除

TagId:0、2、3、4、5

，查找其他行

ParentTagId

中的

TagId

，然后递归查找其他行

我只在下面写了一部分代码，我不知道如何循环保持选择和删除

"TagId" serial NOT NULL,
"Name" character varying,
"ParentTagId" integer,
CONSTRAINT "Tag_pkey" PRIMARY KEY ("TagId")

TagId | Name | ParentTagId
0     |      |    
1     |      |
2     |      |0
3     |      |2
4     |      |3
5     |      |0

-

---

Sql解决方案。

此递归查询为所有

TagId

s选择子ID数组（如

children

）：

with recursive "Tags"("TagId", "ChildId", "Children") as (
    select "TagId", "TagId", array["TagId"]
    from "Tag"
union
    select "Tags"."TagId", "Tag"."TagId", "Tags"."Children"|| "Tag"."TagId"
    from "Tags"
    join "Tag" on "Tags"."ChildId" = "Tag"."ParentTagId"
    ),
"Children" as (
    select "TagId", unnest("Children")
    from "Tags"
    )
select "TagId", array_agg(distinct unnest) "Children"
from "Children"
group by 1
order by 1;

 TagId |  Children
-------+-------------
     0 | {0,2,3,4,5}
     1 | {1}
     2 | {2,3,4}
     3 | {3,4}
     4 | {4}
     5 | {5}
(6 rows)

所以这一个为

TagId=0

选择子项：

with recursive "Tags"("TagId", "ChildId", "Children") as (
    select "TagId", "TagId", array["TagId"]
    from "Tag"
union
    select "Tags"."TagId", "Tag"."TagId", "Tags"."Children"|| "Tag"."TagId"
    from "Tags"
    join "Tag" on "Tags"."ChildId" = "Tag"."ParentTagId"
    ),
"Children" as (
    select "TagId", unnest("Children")
    from "Tags"
    )
select array_agg(distinct unnest) "Children"
from "Children"
where "TagId" = 0

  Children
-------------
 {0,2,3,4,5}
(1 row) 

最后，此查询删除

TagId=0

及其所有子项：

with recursive "Tags"("TagId", "ChildId", "Children") as (
    select "TagId", "TagId", array["TagId"]
    from "Tag"
union
    select "Tags"."TagId", "Tag"."TagId", "Tags"."Children"|| "Tag"."TagId"
    from "Tags"
    join "Tag" on "Tags"."ChildId" = "Tag"."ParentTagId"
    ),
"Children" as (
    select "TagId", unnest("Children")
    from "Tags"
    )
delete from "Tag"
where "TagId" in (
    select distinct unnest
    from "Children"
    where "TagId" = 0
    )
returning *;

 TagId | Name | ParentTagId
-------+------+-------------
     2 |      |           0
     0 |      |
     4 |      |           3
     3 |      |           2
     5 |      |           0
(5 rows)


DELETE 5

with recursive "Tags"("TagId", "ChildId", "Children") as (
    select "TagId", "TagId", array["TagId"]
    from "Tag"
union
    select "Tags"."TagId", "Tag"."TagId", "Tags"."Children"|| "Tag"."TagId"
    from "Tags"
    join "Tag" on "Tags"."ChildId" = "Tag"."ParentTagId"
    ),
"Children" as (
    select "TagId", unnest("Children")
    from "Tags"
    )
select array_agg(distinct unnest) "Children"
from "Children"
where "TagId" = 0

  Children
-------------
 {0,2,3,4,5}
(1 row) 

with recursive "Tags"("TagId", "ChildId", "Children") as (
    select "TagId", "TagId", array["TagId"]
    from "Tag"
union
    select "Tags"."TagId", "Tag"."TagId", "Tags"."Children"|| "Tag"."TagId"
    from "Tags"
    join "Tag" on "Tags"."ChildId" = "Tag"."ParentTagId"
    ),
"Children" as (
    select "TagId", unnest("Children")
    from "Tags"
    )
delete from "Tag"
where "TagId" in (
    select distinct unnest
    from "Children"
    where "TagId" = 0
    )
returning *;

 TagId | Name | ParentTagId
-------+------+-------------
     2 |      |           0
     0 |      |
     4 |      |           3
     3 |      |           2
     5 |      |           0
(5 rows)


DELETE 5