【大数据入门实践】Hive DDL

1:hive 创建一个数据库
hive> CREATE DATABASE zhdc;
OK
Time taken: 0.22 seconds
hive> 

2:hive 查看数据库列表
hive> SHOW DATABASES;
OK
default
zhdc
Time taken: 0.032 seconds, Fetched: 2 row(s)

3:hive 存在 hdfs 什么地方?
hive> DESC DATABASE zhdc;
OK
zhdc		hdfs://localhost:9000/user/hive/warehouse/zhdc.db	hadoop	USER	
Time taken: 0.032 seconds, Fetched: 1 row(s)

1:hive元数据
mysql> show tables;
+---------------------------+
| Tables_in_ruoze_d6        |
+---------------------------+
| bucketing_cols            |
| cds                       |
| columns_v2                |
| database_params           |
| dbs                       |
| func_ru                   |
| funcs                     |
| global_privs              |
| part_col_stats            |
| partition_key_vals        |
| partition_keys            |
| partition_params          |
| partitions                |
| roles                     |
| sd_params                 |
| sds                       |
| sequence_table            |
| serde_params              |
| serdes                    |
| skewed_col_names          |
| skewed_col_value_loc_map  |
| skewed_string_list        |
| skewed_string_list_values |
| skewed_values             |
| sort_cols                 |
| tab_col_stats             |
| table_params              |
| tbls                      |
| version                   |
+---------------------------+
29 rows in set (0.00 sec)

2:dbs
mysql> select * from dbs;
+-------+-----------------------+---------------------------------------------------+---------+------------+------------+
| DB_ID | DESC                  | DB_LOCATION_URI                                   | NAME    | OWNER_NAME | OWNER_TYPE |
+-------+-----------------------+---------------------------------------------------+---------+------------+------------+
|     1 | Default Hive database | hdfs://localhost:9000/user/hive/warehouse         | default | public     | ROLE       |
|     6 | NULL                  | hdfs://localhost:9000/user/hive/warehouse/zhdc.db | zhdc    | hadoop     | USER       |
+-------+-----------------------+---------------------------------------------------+---------+------------+------------+
2 rows in set (0.00 sec)

mysql> 

1:格式化查询数据
mysql> select * from dbs \G;
*************************** 1. row ***************************
          DB_ID: 1
           DESC: Default Hive database
DB_LOCATION_URI: hdfs://localhost:9000/user/hive/warehouse
           NAME: default
     OWNER_NAME: public
     OWNER_TYPE: ROLE
*************************** 2. row ***************************
          DB_ID: 6
           DESC: NULL
DB_LOCATION_URI: hdfs://localhost:9000/user/hive/warehouse/zhdc.db
           NAME: zhdc
     OWNER_NAME: hadoop
     OWNER_TYPE: USER
2 rows in set (0.00 sec)

1:创建表
create table emp(
empno int,
ename string,
job string,
mgr int,
hiredate string,
sal double,
comm double,
deptno int
) ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t';

2:执行
hive> create table emp(
    > empno int,
    > ename string,
    > job string,
    > mgr int,
    > hiredate string,
    > sal double,
    > comm double,
    > deptno int
    > ) ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t';
OK
Time taken: 0.37 seconds
hive> show tables;
OK
emp
Time taken: 0.036 seconds, Fetched: 1 row(s)
hive>