oracle中 unino，union all,minus,intersect的用法

1.准备测试数据

create table test_minus_tbl(
id varchar2(20),
name varchar2(50),
age int
);

alter table test_minus_tbl add constraint pk_minus_tbl primary key(id);

create sequence seq_test_minus_tbl increment by 1 start with 1 maxvalue 99999999 minvalue 1 nocycle nocache;

insert into test_minus_tbl(id, name, age)values(seq_test_minus_tbl.nextval, 'lxl', 26);
insert into test_minus_tbl(id, name, age)values(seq_test_minus_tbl.nextval, 'lxl', 26);
insert into test_minus_tbl(id, name, age)values(seq_test_minus_tbl.nextval, 'lxl_01', 26);
insert into test_minus_tbl(id, name, age)values(seq_test_minus_tbl.nextval, 'lxl_02', 26);
insert into test_minus_tbl(id, name, age)values(seq_test_minus_tbl.nextval, 'lxl_01', 26);
insert into test_minus_tbl(id, name, age)values(seq_test_minus_tbl.nextval, 'lxl_02', 26);

2.进行测试

select * from test_minus_tbl;

minus的作用及用法，两个结果集相减

select t.name
from test_minus_tbl t
minus
select t1.name from test_minus_tbl t1 where t1.name = 'lxl';

union all的作用及用法，两个结果集合并，不去重

select t.name
from test_minus_tbl t
union all
select t1.name from test_minus_tbl t1;

union的作用及用法，两个结果集合并，并且去掉重复的记录，让重复的记录只显示一条

select t.name
from test_minus_tbl t
union
select t1.name from test_minus_tbl t1;

intersect的作用及用法，求交集

select t.name
from test_minus_tbl t
intersect
select t1.name from test_minus_tbl t1 where t1.name = 'lxl';