hive的库及表的基本操作

一.数据库操作

1.创建数据库

create database financials;

2.创建数据库，避免抛出错误信息

create database if not exists financials;

3.查看hive中包含的数据库

show databases;

4.显示当前所在数据库

use financials ;

5.删除空数据库

drop database if exists financials;

6.删除有表格的数据库

drop database if exists financials cascade;

7.修改数据库

alter database financials  set dbproperties (`edited-by`=`job dba`);

二.  创建表

1.创建内部表

CREATE TABLE if not exists financials.employees1(

name STRING COMMENT 'Empolyee name',

salary FLOAT COMMENT 'Empolyee salary',

subordinates ARRAY<STRING> COMMENT 'Names of subordinates',

duduction MAP<STRING,FLOAT>

COMMENT 'Keys are deductions names,vlaues are percentages',

address STRUCT<street:STRING,city:STRING,state:STRING,zip:INT>

COMMENT 'Home address')

COMMENT 'Description ofthe table'

LOCATION '/user/hive/warehouse/financials.db/employees'

TBLPROPERTIES('creator'='li','created_at'='2014-1-23 10:00:00');

2.创建外部表

CREATE  EXTERNAL TABLE financials.employees2(
ts String,
uid String,
keyword String,
rank int,
order int,
url String)
comment 'this