表的修改
1.alter table 修改表的元数据：
a.修改表名称
hive>alter table student rename to student1;
b.修改表分区
hive>alter table hive.logs add partition (dt='2018-9-1',country='beijng');
hive>alter table hive.logs drop partition (dt='2018-9-1',country='beijng');
c.添加列
hive>alter table hive.logs add columns(id int,name string);
d.删除和替换列
hive>alter table hive.logs replace columns (id int,name string);
向管理表装载数据
1.装载数据
hive>load data [local] inpath '/data/hive' [overwrite] into table tbname;
说明：含local关键字：加载本地目录数据到warehouse下；如果不含local关键字，加载数据目录默认为hdfs路径。
2.通过查询语句向表中插入数据:在原始数据的基础上，进行业务分析后生成的表数据
hive>insert overwrite table new_table select [column字段] from 原始数据表 where 条件；
或
hive> from 原始数据表 别名 insert overwrite table new_table select [column字段] where 条件；
3.创建表时，也可以执行插入数据
hive>create table new_table as select id,name,age from student where age>23;
4.导出数据
hive>insert overwrite directory '/data/stocks/2009-6-23' select * from stocks where ymd ='2009=6-23';
查询
1.对array查询
hive>select name,subordinates[1] from hive.employees where name='John Doe';
2.对map查询
hive>select name,deductions['State Taxes'] from hive.employees where name = 'John Doe';
3.对struct查询
hive>select name,address.state from hive.employees where name ='John Doe';
4.支持运算符
5.内置函数，比如sum(),count(),avg()等。
6.limit
hive>select upper(name),salary,deductions['Federal Taxes'],round(salary*(1-deductions['Federal Taxes'])) from hive.employees limit 6;
7.列别名
hive>select upper(name),salary,deductions['Federal Taxes'] as Taxes,round(salary*(1-deductions['Federal Taxes'])) as sal from hive.employees limit 6;
8.嵌套
hive>from (select upper(name) as name,salary,deductions['Federal Taxes'] as Taxes,round(salary*(1-deductions['Federal Taxes'])) as sal from hive.employees) e select e.name,e.Taxes,e.sal where e.sal >70000;
本地执行条件
1.简单查询：select * from table；
2.将分区列作为查询条件，但查询列应为“*”；
3.调优方案：建议将hive.exec.mode.local.auto=true;并添加至{/home/hyxy/.hiverc}中；
group by
hive>select year(ymd),avg(price_close) from stocks where exchange1='NASDAQ' and symbol = 'AAPL' group by year(ymd);
说明：分组属性列在mysql中一定要出现在select子句之后；但在hive中不需要。