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create table person (pid int,name varchar2(20) unique,
age int check(age between 0 and 150),sex varchar(4) default 'ÄÐ',tp int,
address varchar(200),constraint person_pid_pk primary key(pid));
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insert into person values(0011,'ÁõÈý½ã',25,'ÄÐ',13930123021,'ºÓ±±Ê¡ÇúÑôÏØ');
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create table book(bid int primary key not null,bname varchar2(20),bprice number(5,2),pid int,
constraint person_book_pid_fk foreign key(pid) references person(pid));
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insert into book values(0101,'¼ò°®',7.85,0011);
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select * from dept;
insert into dept values(50,'HR','HOUSTON');
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insert into emp(empno,ename,job,sal,mgr,hiredate,comm,deptno)
values(8888,'ÕÅÈý','¾Àí',9000,null,sysdate,null,50);
ROWNUM
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select rownum,empno,ename,job,sal,hiredate
from emp where rownum<=5;
select * from
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(select rownum rn,empno,ename,job,sal,hiredate from emp
where rownum <=10 ) temp
where temp.rn>5;
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ALTER TABLE SCHEMA.PREFIX_INFO ADD (
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alter table schema.prefix_info add constraint prefix_info_pkey primary key(info_id);
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