--检查约束
create table test1(
       id number(10) primary key,email varchar2(10) check (email like ‘%@%‘)
)
drop table test1
insert into test1 values(1,‘[email protected]‘);
select * from test1

create table test2(
       id number primary key,gender varchar2(4) check(gender in(‘男‘,‘女‘))
)
drop table test2
select * from test2
insert into test2 values(1,‘男‘)