Hive 安装及测试二

比眉伴天荒 2022-08-09 03:11 164阅读 0赞

上一节我们演示了hive的安装，下面我们通过命令行的方式演示一下hive的应用。

进入命令行

bin/hive

1.查看所有表

>show tables;

2.创建表，并指定每行数据的列分隔符

>CREATE TABLE t\_hive (id int,name string) ROW FORMAT DELIMITED FIELDS TERMINATED BY '\\t';

3.查看表结构

> desc t\_hive;

hive> desc t_hive;
    OK
    id                      int                                         
    name                    string                                      
    Time taken: 0.242 seconds, Fetched: 2 row(s)

4.导入文本数据

创建如下文件

[hadoop@study-90 ~]$ cat /home/hadoop/t_hive.txt
    1       aaa
    2       bbb
    3       ccc
    4       ddd

>LOAD DATA LOCAL INPATH '/home/hadoop/t\_hive.txt' OVERWRITE INTO TABLE t\_hive ;

5.查询表数据

hive> select * from t_hive;
    OK
    1       aaa
    2       bbb
    3       ccc
    4       ddd
    Time taken: 0.295 seconds, Fetched: 4 row(s)

hive> 
        > 
        > select * from t_hive where id=2;
    OK
    2       bbb
    Time taken: 5.904 seconds, Fetched: 1 row(s)

6.复制表结构

create table t\_hive1 LIKE t\_hive;

7.复制表数据

INSERT OVERWRITE TABLE t\_hive1 SELECT \* FROM t\_hive ;

hive> INSERT OVERWRITE TABLE t_hive1 SELECT * FROM t_hive ;
    Query ID = hadoop_20151008023154_d6decee5-2900-461d-a706-4195b9626711
    Total jobs = 3
    Launching Job 1 out of 3
    Number of reduce tasks is set to 0 since there's no reduce operator
    Starting Job = job_1444271460174_0001, Tracking URL = http://study-90:8088/proxy/application_1444271460174_0001/
    Kill Command = /home/hadoop/hadoop-2.6.0/bin/hadoop job  -kill job_1444271460174_0001
    Hadoop job information for Stage-1: number of mappers: 1; number of reducers: 0
    2015-10-08 02:34:33,496 Stage-1 map = 0%,  reduce = 0%
    2015-10-08 02:35:14,243 Stage-1 map = 100%,  reduce = 0%, Cumulative CPU 1.84 sec
    MapReduce Total cumulative CPU time: 1 seconds 840 msec
    Ended Job = job_1444271460174_0001
    Stage-4 is selected by condition resolver.
    Stage-3 is filtered out by condition resolver.
    Stage-5 is filtered out by condition resolver.
    Moving data to: hdfs://mycluster/user/hive/warehouse/t_hive1/.hive-staging_hive_2015-10-08_02-31-54_835_5493803551258585988-1/-ext-10000
    Loading data to table default.t_hive1
    Table default.t_hive1 stats: [numFiles=1, numRows=4, totalSize=24, rawDataSize=20]
    MapReduce Jobs Launched: 
    Stage-Stage-1: Map: 1   Cumulative CPU: 1.84 sec   HDFS Read: 3148 HDFS Write: 95 SUCCESS
    Total MapReduce CPU Time Spent: 1 seconds 840 msec
    OK
    Time taken: 210.383 seconds

hive> select * from t_hive1
        > ;
    OK
    1       aaa
    2       bbb
    3       ccc
    4       ddd
    Time taken: 0.832 seconds, Fetched: 4 row(s)

8.删除表

drop table t\_hive1;

详细请参考：[hive用户指南][hive]

[hive]: http://download.csdn.net/detail/tianwei7518/9163609