PostgreSQL递归查询

原料

--创建组织架构表
create table "Org"(
    "OrgId" character varying(50) primary key,
    "ParentId" character varying(50),
    "OrgName" character varying(50)
)
--添加数据
insert into "Org" ("OrgId","ParentId","OrgName") values('',null,'***集团');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','子公司01');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','子公司02');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','子公司03');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','子公司04');

insert into "Org" ("OrgId","ParentId","OrgName") values('','','电子商务部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','渠道合作部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','个人业务部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','人力资源部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','运营管理部');

insert into "Org" ("OrgId","ParentId","OrgName") values('','','电子商务部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','渠道合作部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','个人业务部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','人力资源部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','运营管理部');

insert into "Org" ("OrgId","ParentId","OrgName") values('','','电子商务部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','渠道合作部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','个人业务部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','人力资源部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','运营管理部');

insert into "Org" ("OrgId","ParentId","OrgName") values('','','电子商务部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','渠道合作部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','个人业务部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','人力资源部');
insert into "Org" ("OrgId","ParentId","OrgName") values('','','运营管理部');

向下递归

--向下递归
with recursive T ("OrgId", "ParentId", "OrgName", "Depth")  AS
(
    select "OrgId", "ParentId", "OrgName", 1 "Depth" from "Org" where "OrgId"=''  --起始节点
    union all
    select  D."OrgId", D."ParentId", D."OrgName", T."Depth" + 1 "Depth" from "Org" D join T on D."ParentId" = T."OrgId"
)
select "OrgId", "ParentId", "OrgName", "Depth" from T

输出结果：

向上递归

--向上递归
with recursive T ("OrgId", "ParentId", "OrgName", "Depth")  AS
(
    select "OrgId", "ParentId", "OrgName", 1 "Depth" from "Org" where "OrgId"=''  --起始节点
    union all
    select  D."OrgId", D."ParentId", D."OrgName", T."Depth" + 1 "Depth" from "Org" D join T on D."OrgId" = T."ParentId"
)
select "OrgId", "ParentId", "OrgName", "Depth" from T

输出结果：