CREATE SEQUENCE public.tab_id_seq
  INCREMENT 1
  MINVALUE 1
  MAXVALUE 9223372036854775807
  START 1
  CACHE 1;
  
CREATE TABLE public.tab
(
  id integer NOT NULL DEFAULT nextval('tab_id_seq'::regclass), -- Код
  parent_id integer, -- Код родителя
  name character varying(1000), -- Наименование
  type_id integer,
  CONSTRAINT tab_pkey PRIMARY KEY (id),
  CONSTRAINT tab_parent_id_fkey FOREIGN KEY (parent_id)
      REFERENCES public.tab (id) MATCH SIMPLE
      ON UPDATE CASCADE ON DELETE CASCADE
)
WITH (
  OIDS=FALSE
);

insert into tab(id,parent_id,name,type_id)values(1,null,'дерево1',1);
insert into tab(id,parent_id,name,type_id)values(2,null,'дерево2',1);
insert into tab(id,parent_id,name,type_id)values(3,1,'дерево11',1);
insert into tab(id,parent_id,name,type_id)values(4,1,'дерево12',1);
insert into tab(id,parent_id,name,type_id)values(5,4,'дерево121',1);
insert into tab(id,parent_id,name,type_id)values(6,4,'дерево122',1);
insert into tab(id,parent_id,name,type_id)values(7,1,'дерево13',1);
insert into tab(id,parent_id,name,type_id)values(8,2,'дерево21',1);
insert into tab(id,parent_id,name,type_id)values(9,2,'дерево22',1);
insert into tab(id,parent_id,name,type_id)values(10,2,'дерево23',1);
insert into tab(id,parent_id,name,type_id)values(11,2,'дерево24',1);

WITH RECURSIVE temp1
(id, parent_id, name, LEVEL ) AS (
SELECT T1.id, T1.parent_id, T1.name, 1
    FROM tab T1 
	WHERE T1.parent_id IS NULL
union
select T2.id, T2.parent_id, T2.name ,LEVEL + 1
     FROM tab T2 
INNER JOIN temp1 ON( temp1.id = T2.parent_id)
)
insert into tab (id, parent_id, name,type_id)
select id+11 as id,  parent_id+11 as parent_id, name, 2 as type_id
from temp1