目录
1.打开并使用数据库
use 活期存款
2.查询表中所有记录
select * from 储户
select 账号,姓名,存款额 from 储户
3.比较跟范围运算
select 账号,姓名,存款额 from 储户
where 存款额>=2000 and 存款额<=5000
select 账号,姓名,存款额 from 储户
where 存款额 between 2000 and 5000
4.查询带计算的列
select 账号,姓名,电话,地址,存款额*0.3 as 利息金 from 储户
where 账号=10011
5.列表查询
select 账号,姓名,存款额 from 储户
where 地址 in('柳南','官塘')
6.空值查询
select * from 储户
where 电话 is null
7.模式匹配
select 账号,姓名,存款额 from 储户
where 姓名 like('刘%')
8.消除重复值
select distinct 储蓄所编号 from 存取款单
9.查询“储户”表中存款额最高的两名储户信息
select top 2 * from 储户
order by 存款额 desc --order by 排序 desc降序asc升序
10.统计“储户”表中存款额的最高值、最低值和平均值
select MAX(存款额) as 最高存款额,
MIN(存款额) as 最低存款额,
AVG(存款额) as 平均存款额 from 储户
11.统计“储户”表中每个地区的储户数和平均存款额
select 账号,COUNT(*)as 储户数,AVG(存款额) as 平均存款额
from 储户
group by 账号
12.统计“储户”表中各地区中储户平均存款额在以上的地区、储户数和平均存款额
select 地址,COUNT(*) as 储户数,AVG(存款额) as 平均存款额
from 储户
group by 地址
having AVG(存款额)>=3000
13.内连接
select a.账号,a.姓名,b.储蓄所编号,b.存取标志,b.存取金额
from 储户 as a,存取款单 as b
where a.账号=b.账号 --或用inner join和on
14.查询“储户”表中每个储户的账号、姓名、存款额以及比其存款额高的其它储户的平均存款额
select a.账号,a.姓名,a.存款额,AVG(b.存款额) as 平均存款额
from 储户 as a,储户 as b
where a.存款额<b.存款额
group by 账号,姓名,存款额
15.左外连接(left join)
select a.账号,a.姓名,b.储蓄所编号,b.存取标志,b.存取金额
from 储户 as a left join 存取款单 as b
on a.账号=b.账号
16.右外连接(right join)
select a.账号,a.姓名,b.储蓄所编号,b.存取标志,b.存取金额
from 储户 as a right join 存取款单 as b
on a.账号=b.账号
17.完全连接(full join)
select a.账号,a.姓名,b.储蓄所编号,b.存取标志,b.存取金额
from 储户 as a full join 存取款单 as b
on a.账号=b.账号
18.子查询
select * from 储户
where 存款额>(select AVG(存款额) from 储户)
select 账号,姓名,地址,存款额 from 储户
where 存款额>
(select 存款额 from 储户
where 地址='柳南')
19.使用子查询检索年之前办理了存取款业务的储户账号、姓名和地址
select a.账号,姓名,地址,存取日期
from 储户 as a left join 存取款单 as b
on a.账号=b.账号
where b.存取日期<(select 存取日期 from 存取款单where b.存取日期<2030)
select * from 储户
where exists
(select * from 存取款单
where 账号=储户.账号)
20.把储户中的所有记录添加到新表中
select * into 储户 from 储户
drop table 储户