MySQL的简单查询语句
查询:
一:查询所有数据
select * from info 查所有数据
select code,name from info 查特定列
二:根据条件查
select * from info where code='p001' 一个条件查询
select * from info where code='p001' and nation='n001' 多条件 并关系 查询
select * from info where name='胡军' or nation='n001' 多条件 或关系 查询
select * from car where price>=50 and price<=60 范围查询
select * from car where price between 50 and 60 范围查询
三:模糊查询
select * from car where name like '%型' %通配符代表任意多个字符
select * from car where name like '%奥迪%' _通配符代表任意一个字符
select * from car where name like '_马%'
四:排序
select * from car order by price asc 按照价格升序排列
select * from car order by price desc 按照价格降序排列
select * from car order by price,oil 按照两列进行排序,前面的为主要的
五:统计函数(聚合函数)
select count(code) from car 查询表中有多少条数据
select max(price) from car 取价格的最大值
select min(price) from car 取价格的最小值
select sum(price) from car 取价格的总和
select avg(price) from car 取价格的平均值
六:分组查询
select brand from car group by brand having count(*)>2 查询所有系列中数量大于2的
七:分页查询
select * from car limit 0,5 跳过几条数据取几条数据
八:去重查询
select distinct brand from car