create table TREE
(
TREEID VARCHAR2(20) not null,
LABLE VARCHAR2(50) not null,
PARENTID VARCHAR2(20)
);
--创建主键
alter table TREE add constraint PK_TREE primary key (TREEID);
--创建表内外键
alter table TREE add constraint FK_TREE foreign key (PARENTID) references TREE (TREEID);

--准备测试数据

insert into TREE (TREEID, LABLE, PARENTID) values ('140000', '山西省', null);
insert into TREE (TREEID, LABLE, PARENTID) values ('140100', '太原市', '140000');
insert into TREE (TREEID, LABLE, PARENTID) values ('140101', '市辖区', '140100');
insert into TREE (TREEID, LABLE, PARENTID) values ('140105', '小店区', '140100');
insert into TREE (TREEID, LABLE, PARENTID) values ('140106', '迎泽区', '140100');
insert into TREE (TREEID, LABLE, PARENTID) values ('140107', '杏花岭区', '140100');
insert into TREE (TREEID, LABLE, PARENTID) values ('140108', '尖草坪区', '140100');
insert into TREE (TREEID, LABLE, PARENTID) values ('140109', '万柏林区', '140100');
insert into TREE (TREEID, LABLE, PARENTID) values ('140110', '晋源区', '140100');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121', '清徐县', '140100');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121100', '清源镇', '140121');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121101', '徐沟镇', '140121');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121102', '东于镇', '140121');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121103', '孟封镇', '140121');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200', '马峪乡', '140121');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200200', '李家楼村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200201', '仁义村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200202', '东马峪村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200203', '西马峪村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200204', '都沟村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200205', '东梁泉村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200206', '西梁泉村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200207', '刘家元村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200208', '梁泉岭村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200209', '圪垛儿村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200210', '西沟村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200211', '桃园村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200212', '阳圈峁村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200213', '枣坪村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200214', '黄土坡村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200215', '杏旺村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200216', '东迎南风村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200217', '西迎南风村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200218', '后窑村委会', '140121200');
insert into TREE (TREEID, LABLE, PARENTID) values ('140121200219', '涧沟村委会', '140121200')