#1. 创建数据库dbtest11
CREATE DATABASE IF NOT EXISTS dbtest11 CHARACTER SET 'utf8';
#2. 运行以下脚本创建表my_employees
USE dbtest11;
CREATE TABLE my_employees(
id INT(10),
first_name VARCHAR(10),
last_name VARCHAR(10),
userid VARCHAR(10),
salary DOUBLE(10,2)
);
CREATE TABLE users(
id INT,
userid VARCHAR(10),
department_id INT
);
#3. 显示表my_employees的结构
USE dbtest11;
DESC my_employees;
DESC users;
#4. 向my_employees表中插入下列数据
ID FIRST_NAME LAST_NAME USERID SALARY
1 patel Ralph Rpatel 895
2 Dancs Betty Bdancs 860
3 Biri Ben Bbiri 1100
4 Newman Chad Cnewman 750
5 Ropeburn Audrey Aropebur 1550
SELECT *
FROM my_employees;
INSERT INTO my_employees VALUES
#values(1,'patel','Ralph','Rpatel',895),
(2,'Dancs','Betty','Bdancs',860),
(3,'Biri','Ben','Bbiri',1100),
(4 ,'Newman','Chad','Cnewman',750),
(5,'Ropeburn','Audrey','Aropebur',1500);
#5. 向users表中插入数据
1 Rpatel 10
2 Bdancs 10
3 Bbiri 20
4 Cnewman 30
5 Aropebur 40
select * from
users
insert into users values
(1,'Rpatel',10),
(2,'Bdancs',10),
(3,'Bbiri',20),
(4,'Cnewman',30),
(5,'Aropebur',40);
#6. 将3号员工的last_name修改为“drelxer”
update my_employees
set last_name = 'drelxer'
where id = 3
#7. 将所有工资少于900的员工的工资修改为1000
update my_employees
set salary = 1000
where salary < 900;
#8. 将userid为Bbiri的user表和my_employees表的记录全部删除
#方式1:
delete from my_employees
where userid = 'Bbiri';
delete from users
where userid = 'Bbiri'
#方式2:
delete m,u
from my_employees m
join users u
on m.userid = u.userid
where m.userid = 'Bbiri'
select * from my_employees;
select * from users;
#9. 删除my_employees、users表所有数据
delete from my_employees;
delete from users;
#10. 检查所作的修正
SELECT * FROM my_employees;
SELECT * FROM users;
#11. 清空表my_employees
truncate table my_employees;
##################################################################
#练习2:
# 1. 使用现有数据库dbtest11
use dbtest11;
# 2. 创建表格pet
create table pet(
name varchar(20),
owner varchar(20),
species varchar(20),
sex char(1),
birth year,
death year
);
desc pet;
# 3. 添加记录
insert into pet values
('Fluffy','harold','Cat','f','2003','2010'),
('Claws','gwen','Cat','m','2004',null),
('Buffy',null,'Dog','f','2009',null),
('Fang','benny','Dog','m','2000',null),
('bowser','diane','Dog','m','2003','2009'),
('Chirpy',null,'Bird','f','2008',null);
select *
from pet;
# 4. 添加字段:主人的生日owner_birth DATE类型。
alter table pet
add owner_birth date
# 5. 将名称为Claws的猫的主人改为kevin
update pet
set owner = 'Kevin'
where name = 'Claws' and species = 'cat'
# 6. 将没有死的狗的主人改为duck
update pet
set owner = 'duck'
where death is null and species = 'dog'
# 7. 查询没有主人的宠物的名字；
select name
from pet
where owner is null;
# 8. 查询已经死了的cat的姓名，主人，以及去世时间；
select name,owner,death
from pet
where death is not null
# 9. 删除已经死亡的狗
delete from pet
where death is not null
and species = 'Dog'
# 10. 查询所有宠物信息
select *
from pet;
########################################################
练习3：
# 1. 使用已有的数据库dbtest11
use dbtest11
# 2. 创建表employee，并添加记录
CREATE TABLE employee(
id INT,
`name` VARCHAR(20),
sex VARCHAR(2),
tel VARCHAR(20),
addr VARCHAR(50),
salary DOUBLE
);
INSERT INTO employee(id,`name`,sex,tel,addr,salary)VALUES
(10001,'张一一','男','13456789000','山东青岛',1001.58),
(10002,'刘小红','女','13454319000','河北保定',1201.21),
(10003,'李四','男','0751-1234567','广东佛山',1004.11),
(10004,'刘小强','男','0755-5555555','广东深圳',1501.23),
(10005,'王艳','男','020-1232133','广东广州',1405.16);
select * from employee
# 3. 查询出薪资在1200~1300之间的员工信息。
select *
from employee
where salary > 1200 and salary < 1300;
# 4. 查询出姓“刘”的员工的工号，姓名，家庭住址。
select id,name,addr
from employee
where name like '刘%';
# 5. 将“李四”的家庭住址改为“广东韶关”
update employee
set addr = '广东韶关'
where name = '李四'
# 6. 查询出名字中带“小”的员工
select *
from employee
where name like '%小%'
)
)
