学习DDL语句
创建对象的语句
Create/Drop/Alter Database
Create Database
CREATE (DATABASE|SCHEMA) [IF NOT EXISTS] database_name [COMMENT database_comment] [LOCATION hdfs_path] [WITH DBPROPERTIES (property_name=property_value, …)];
Drop Database
DROP (DATABASE|SCHEMA) [IF EXISTS] database_name [RESTRICT|CASCADE];
Alter Database
ALTER (DATABASE|SCHEMA) database_name SET DBPROPERTIES (property_name=property_value, …); ALTER (DATABASE|SCHEMA) database_name SET OWNER [USER|ROLE] user_or_role;
Use Database USE database_name; USE DEFAULT;
Hive运行的时候，元数据存储在关系系数据库里面。
Hive运行的时候需要有映射关系的数据，需要快速地读取
Linux里面其实有自带的关系数据库，但是十分不稳定，所以我们不用这个数据库
我们自己搭建一个关系数据库
安装一个关系数据库（mysql）
我们在安装Linux的时候已经安装了mysql
启动mysql
查看mysql是否已经进行监听
3306端口，对的
连接mysql
受限我们需要驱动
设置mysql中远程登录的问题
输入use mysql select * from user;
grant all on . to root@’%’ identified by ‘123456’; 这个是给所有的用户在所有的数据库上的所有的表的所有权限，密码是123456
查看一下是否成功
修改配置文件
配置mysql路径
修改用户名和密码
我们创建一个hive的数据库
进入hive
启动之后推出hive
Quite；
然后在mysql中查看表
退出
学习hive的DDL语句
Create Table
CREATE [TEMPORARY] [EXTERNAL] TABLE [IF NOT EXISTS] [db_name.]table_name — (Note: TEMPORARY available in Hive 0.14.0 and later) [(col_name data_type [COMMENT col_comment], …)] [COMMENT table_comment] [PARTITIONED BY (col_name data_type [COMMENT col_comment], …)] [CLUSTERED BY (col_name, col_name, …) [SORTED BY (col_name [ASC|DESC], …)] INTO num_buckets BUCKETS] [SKEWED BY (col_name, col_name, …)– (Note: Available in Hive 0.10.0 and later)]ON ((col_value, col_value, …), (col_value, col_value, …), …)[STORED AS DIRECTORIES] [ [ROW FORMAT row_format][STORED AS file_format]| STORED BY ‘storage.handler.class.name’ [WITH SERDEPROPERTIES (…)] — (Note: Available in Hive 0.6.0 and later) ] [LOCATION hdfs_path] [TBLPROPERTIES (property_name=property_value, …)] — (Note: Available in Hive 0.6.0 and later) [AS select_statement]; — (Note: Available in Hive 0.5.0 and later; not supported for external tables)CREATE [TEMPORARY] [EXTERNAL] TABLE [IF NOT EXISTS] [db_name.]table_name LIKE existing_table_or_view_name [LOCATION hdfs_path];data_type : primitive_type | array_type | map_type | struct_type | union_type — (Note: Available in Hive 0.7.0 and later)primitive_type : TINYINT | SMALLINT | INT | BIGINT | BOOLEAN | FLOAT | DOUBLE | STRING | BINARY– (Note: Available in Hive 0.8.0 and later) | TIMESTAMP — (Note: Available in Hive 0.8.0 and later) | DECIMAL– (Note: Available in Hive 0.11.0 and later) | DECIMAL(precision, scale) — (Note: Available in Hive 0.13.0 and later) | DATE– (Note: Available in Hive 0.12.0 and later) | VARCHAR– (Note: Available in Hive 0.12.0 and later) | CHAR– (Note: Available in Hive 0.13.0 and later)array_type : ARRAY < data_type >map_type : MAP < primitive_type, data_type >struct_type : STRUCT < col_name : data_type [COMMENT col_comment], …>union_type : UNIONTYPE < data_type, data_type, … > — (Note: Available in Hive 0.7.0 and later)row_format : DELIMITED [FIELDS TERMINATED BY char [ESCAPED BY char]] [COLLECTION ITEMS TERMINATED BY char][MAP KEYS TERMINATED BY char] [LINES TERMINATED BY char][NULL DEFINED AS char] — (Note: Available in Hive 0.13 and later) | SERDE serde_name [WITH SERDEPROPERTIES (property_name=property_value, property_name=property_value, …)]file_format: : SEQUENCEFILE | TEXTFILE — (Default, depending on hive.default.fileformat configuration) | RCFILE– (Note: Available in Hive 0.6.0 and later) | ORC– (Note: Available in Hive 0.11.0 and later) | PARQUET– (Note: Available in Hive 0.13.0 and later) | AVRO– (Note: Available in Hive 0.14.0 and later) | INPUTFORMAT input_format_classname OUTPUTFORMAT output_format_classname正如我总是意犹未尽的想起你。
