-- 보기 1 (O)
create table emp_3879 ( empno3, ename3, sal3, deptno3 )
as
select empno, ename, sal, deptno
from emp
where 1 = 2;
select * from emp_3879;
-- 보기 2 (X)
select table_constraints
from emp_3879;
select *
from dictionary
where table_name LIKE '%CONSTRAINTS';
select *
from USER_CONSTRAINTS
WHERE table_name = ('emp_3879');
-- 보기 3 (O) MYSALES has NOT NULL constraints on any selected columns which had that
-- constraint in the SALES table
select *
from USER_CONSTRAINTS
WHERE table_name = ('emp_3879');
alter table emp modify ( sal not null);
create table emp_3879 ( empno3, ename3, sal3, deptno3 )
as
select empno, ename, sal, deptno
from emp
where 1 = 2;
select * from emp_3879;