數據庫簡單的用處（四）
if exists (select * from sysdatabases where name='zhongfei')
drop database zhongfei
go
create database zhongfei
go
use zhongfei
go
create table T_Person (FName varchar(20) primary key,Fage int,FRemark varchar(20));
create table T_Debt(FNumber varchar(20) primary key,FAmount numeric(10,2) not null,FPerson varchar(20),Foreign key(Fperson) references T_Person(Fname));
go
select * from T_Person
select * from t_debt
use master
drop table T_person
drop table T_Debt
insert into T_Person(FName,FAge,FRemark) values('tom','18','usa')
insert into T_Person(FName,FAge,FRemark) values('nanwang','18','usa')
insert into T_Person(FName,FAge,FRemark) values('xiaofeng','18','usa')
insert into T_Person(FName,FAge,FRemark) values('nana','18','usa')
insert into T_Person(FName,FAge,FRemark) values('feifei','20','china')
insert into T_Person values('zhengzheng','17','english')
insert into T_Person values('kuku','19','banana')
insert into T_Person values('shuaishuai','25','china')
insert into T_Debt(FNumber,FPerson) values('1','tom')
insert into T_Debt(FNumber,FAmount,FPerson) values('1','200','tom')
insert into T_Debt(FNumber,FAmount,FPerson) values('2','300','nana')
update T_Person
set FRemark='sunan'
update T_person set Fage =16 where Fname='tom'
update t_person set fage = 13
where fname='nana' or fname='shuaishuai'
update t_person
set fremark='china'
where fname='nana'
update t_debt set famount = 123 where fperson='tom'
delete from t_person
delete from t_debt
delete from t_person
where fage>18 or fremark ='china'
create table t_employee(fnumber varchar(20),fname varchar(20),fage int,fsalary decimal(10,2),primary key(fnumber))
select * from t_employee
insert into t_employee values('edvoo1','tom',25,8300);
insert into t_employee values('edvoo2','nana',21,3500);
insert into t_employee values('edvoo3','leilei',27,3300);
insert into t_employee values('edvoo4','shuaishuai',20,2500.38);
insert into t_employee values('edvoo5','caicai',23,2300);
insert into t_employee values('edvoo6','maomao',25,8300.80);
insert into t_employee values('edvoo7','tom1',25,85300);
select fnumber from t_employee
select fname,fage from t_employee
select fnumber number ,fname name,fage age,fsalary salary from t_employee
select fname,fsalary from t_employee
where fsalary<5000
select fname,fage,fsalary from t_employee
where fsalary>5000 and fage>20
select max(fsalary) salary from t_employee
where fage >25 or fage <30
select avg(fage) from t_employee
where fsalary>3000
select sum(fsalary) from t_employee
select count(*) from t_employee
select * from t_employee order by fage desc
select * from t_employee order by fage asc
select * from t_employee order by fage asc ,fsalary desc
select * from t_employee where fage >22
order by fage asc,fsalary desc
select * from t_employee where fname like 'n%'
select * from t_employee where fname like '%ai'
select * from t_employee where fname like '%a%'
select * from t_employee where fname like '_i'
select * from t_employee where fname like 't[oa]m'
select * from t_employee where fname like '[a-z]ai'
select * from t_employee where fname like 'n[^e]%'
select * from t_employee where fname like '%i'
select * from t_employee where fname like '%a_'
select * from t_employee
where fage <24 and fsalary>2500
select * from t_employee
where not (fage<24) and not fsalary<2500
select fage,fnumber,fname from t_employee
where fage = 20 or fage=25 or fage=27
select fage,fnumber,fname from t_employee
where fage in(20,25,27)
select * from t_employee
where fage between 23 and 27
select * from t_employee
where (fage between 23 and 27)
or(fsalary between 2800 and 6500)