1粒竖、創(chuàng)建數(shù)據(jù)庫python
create database python charset=utf8;
2宏赘、設計班級表結構為id蒋荚、name疾棵、isdelete戈钢,編寫創(chuàng)建表的語句
create table classes(
id int unsigned auto_increment primary key not null,
name varchar(10),
isdelete bit default 0);
向班級表中插入數(shù)據(jù)python1、python2是尔、python3
insert into classes(name) values('python1'),('python2'),('python3');
3殉了、學生表結構設計為:姓名、生日拟枚、性別薪铜、家鄉(xiāng),并且學生表與班級表為多對一的關系恩溅,寫出創(chuàng)建學生表的語句
這里認為 gender 默認值1是表示男生隔箍,isdelete 默認值0表示未刪除
create table students(
id int unsigned auto_increment primary key not null,
name varchar(10) not null,
birthday date,
gender bit default 1,
hometown varchar(20),
clsid int unsigned,
isdelete bit default 0);
4、向學生表中插入數(shù)據(jù):這里認為 gender 默認值1是表示男生
? * python1班有郭靖脚乡、黃蓉蜒滩,要求:使用全列插入,一次一值
? * python2班有楊過奶稠、小龍女俯艰,要求:使用指定列插入,一次一值
? * 未分班的學生有黃藥師窒典、洪七公、洪七婆稽莉,要求:使用指定列插入瀑志,一次多值
insert into students values(0,'郭靖','2016-1-1',1,'蒙古',1,0);
insert into students values(0,'黃蓉','2016-5-8',0,'桃花島',1,0);
insert into students(name,gender,clsid) values('楊過',1,2);
insert into students(name,clsid) values('小龍女',2);
insert into students(name) values('黃藥師'),('洪七公'),('洪七婆');
5、查詢學生的姓名污秆、生日劈猪,如果沒有生日則顯示無
select name,ifnull(birthday,'無') from students;
6、查詢學生的姓名良拼、年齡
select name,year(now()) - year(birthday) as age from students;
7战得、邏輯刪除洪七婆
update students set isdelete=1 where name='洪七婆'
8、修改洪七公的性別為女(gender為0就是女)
update students set gender=0 where name='洪七公'
9庸推、設計科目表subjects常侦,包括科目名稱
create table subjects(
id int unsigned auto_increment primary key not null,
name varchar(20),
isdelete bit default 0);
10浇冰、向表中插入數(shù)據(jù),科目名有:python聋亡、數(shù)據(jù)庫肘习、前端
insert into subjects(name) values('python'),('數(shù)據(jù)庫'),('前端');
11、設計成績表坡倔,字段包括:學生id漂佩、科目id、成績
create table scores(
id int unsigned auto_increment primary key not null,
score int,
stuid int unsigned,
subid int unsigned);
12罪塔、向成績表中添加一些示例數(shù)據(jù)
insert into scores(score,stuid,subid) values
(100,1,1),(98,1,2),(90,1,3),
(95,2,1),(100,2,2),(98,2,3),
(90,3,1),(80,3,2),(85,3,3),
(70,4,1),(60,4,2),(87,4,3);