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875天前create table book ---book表 |
( |
book_id number(4) primary key,--id是自增长的，所以需要使用序列 |
book_name varchar2(30) unique not null, |
book_count number(5) not null,--记录概述被借阅的次数 |
status number(1) check(status in(1,0))--1表示可借，0表示借出 |
); |
create sequence seq_book_id;--序列 |
insert into book(book_id,book_name,book_count,status) values(seq_book_id.nextval,'道德经',0,1); |
insert into book(book_id,book_name,book_count,status) values(seq_book_id.nextval,'金刚经',0,1); |
insert into book(book_id,book_name,book_count,status) values(seq_book_id.nextval,'Java入门',0,1); |
insert into book(book_id,book_name,book_count,status) values(seq_book_id.nextval,'Web入门',0,1); |
insert into book(book_id,book_name,book_count,status) values(seq_book_id.nextval,'三书',0,1); |
insert into book(book_id,book_name,book_count,status) values(seq_book_id.nextval,'项目',0,1); |
select * from book |
--user表 |
create table lib_users |
( |
user_id number(4) primary key,--用户编号，自增长 |
user_name varchar2(30) unique,--用户姓名 |
user_password varchar(20) not null,--用户密码 |
user_type number(1) check(user_type in(1,2))--1表示普通用户，2表示管理员 |
); |
create sequence seq_users_id;--创建序列 |
insert into lib_users(user_id,user_name,user_password,user_type)values(seq_users_id.nextval,'zhangsan','zhangsan',1); |
insert into lib_users(user_id,user_name,user_password,user_type)values(seq_users_id.nextval,'lisi','lisi',1); |
insert into lib_users(user_id,user_name,user_password,user_type)values(seq_users_id.nextval,'laozi','laozi',2); |
select * from lib_users |
--record表 |
create table record |
( |
record_id number(4) primary key, |
user_id number(4) not null, |
book_id number(4) not null, |
lend_time date not null, |
return_time date |
); |
alter table record add constraints record_userid_fk foreign key(user_id) references lib_users(user_id);--外键约束 |
alter table record add constraints record_bookid_fk foreign key(book_id) references book(book_id);--外键约束 |
create sequence seq_record_id;--创建序列 |
insert into record(record_id,user_id,book_id,lend_time,return_time) |
values(seq_record_id.nextval,1,1,to_date('2017-12-12','yyyy-MM_dd'),to_date('2018-1-12','yyyy-MM-dd')) |
insert into record(record_id,user_id,book_id,lend_time,return_time) |
values(seq_record_id.nextval,1,2,to_date('2017-10-11','yyyy-MM-dd'),to_date('2017-11-12','yyyy-MM-dd')); |
insert into record(record_id,user_id,book_id,lend_time,return_time) |
values(seq_record_id.nextval,2,3,to_date('2017-9-11','yyyy-MM-dd'),to_date('2017-10-11','yyyy-MM-dd')); |
insert into record(record_id,user_id,book_id,lend_time,return_time) |
values(seq_record_id.nextval,3,1,to_date('2017-9-15','yyyy-MM-dd'),to_date('2017-10-31','yyyy-MM-dd')); |
insert into record(record_id,user_id,book_id,lend_time,return_time) |
values(seq_record_id.nextval,1,1,to_date('2017-11-11','yyyy-MM-dd'),to_date('2018-2-11','yyyy-MM-dd')); |
insert into record(record_id,user_id,book_id,lend_time,return_time) |
values(seq_record_id.nextval,1,1,to_date('2017-12-11','yyyy-MM-dd'),to_date('2018-5-11','yyyy-MM-dd')); |
select *from record |
初级程序员
by: 234432 发表于：2021-06-16 08:42:17 顶(0) | 踩(0) 回复
感谢
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