HIVE攻略 JFK_Hive安装及使用攻略

目录Hive的安装

Hive的基本使用:CRUD

Hive交互式模式

数据导入

数据导出

Hive查询HiveQL

Hive视图

Hive分区表

1. Hive的安装

系统环境装好hadoop的环境后,我们可以把Hive装在namenode机器上(c1)。hadoop的环境,请参考:让Hadoop跑在云端系列文章,RHadoop实践系列之一:Hadoop环境搭建

下载: hive-0.9.0.tar.gz解压到: /home/cos/toolkit/hive-0.9.0

hive配置~ cd /home/cos/toolkit/hive-0.9.0

~ cp hive-default.xml.template hive-site.xml

~ cp hive-log4j.properties.template hive-log4j.properties

修改hive-site.xml配置文件把Hive的元数据存储到MySQL中~ vi conf/hive-site.xml

javax.jdo.option.ConnectionURL

jdbc:mysql://c1:3306/hive_metadata?createDatabaseIfNotExist=true

JDBC connect string for a JDBC metastore

javax.jdo.option.ConnectionDriverName

com.mysql.jdbc.Driver

Driver class name for a JDBC metastore

javax.jdo.option.ConnectionUserName

hive

username to use against metastore database

javax.jdo.option.ConnectionPassword

hive

password to use against metastore database

hive.metastore.warehouse.dir

/user/hive/warehouse

location of default database for the warehouse

修改hive-log4j.properties#log4j.appender.EventCounter=org.apache.hadoop.metrics.jvm.EventCounter

log4j.appender.EventCounter=org.apache.hadoop.log.metrics.EventCounter

设置环境变量~ sudo vi /etc/environment

PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/home/cos/toolkit/ant184/bin:/home/cos/toolkit/jdk16/bin:/home/cos/toolkit/maven3/bin:/home/cos/toolkit/hadoop-1.0.3/bin:/home/cos/toolkit/hive-0.9.0/bin"

JAVA_HOME=/home/cos/toolkit/jdk16

ANT_HOME=/home/cos/toolkit/ant184

MAVEN_HOME=/home/cos/toolkit/maven3

HADOOP_HOME=/home/cos/toolkit/hadoop-1.0.3

HIVE_HOME=/home/cos/toolkit/hive-0.9.0

CLASSPATH=/home/cos/toolkit/jdk16/lib/dt.jar:/home/cos/toolkit/jdk16/lib/tools.jar

在hdfs上面,创建目录$HADOOP_HOME/bin/hadoop fs -mkidr /tmp

$HADOOP_HOME/bin/hadoop fs -mkidr /user/hive/warehouse

$HADOOP_HOME/bin/hadoop fs -chmod g+w /tmp

$HADOOP_HOME/bin/hadoop fs -chmod g+w /user/hive/warehouse

在MySQL中创建数据库create database hive_metadata;

grant all on hive_metadata.* to hive@'%' identified by 'hive';

grant all on hive_metadata.* to hive@localhost identified by 'hive';

ALTER DATABASE hive_metadata CHARACTER SET latin1;

手动上传mysql的jdbc库到hive/lib~ ls /home/cos/toolkit/hive-0.9.0/lib

mysql-connector-java-5.1.22-bin.jar

启动hive#启动metastore服务

~ bin/hive --service metastore &

Starting Hive Metastore Server

#启动hiveserver服务

~ bin/hive --service hiveserver &

Starting Hive Thrift Server

#启动hive客户端

~ bin/hive shell

Logging initialized using configuration in file:/root/hive-0.9.0/conf/hive-log4j.properties

Hive history file=/tmp/root/hive_job_log_root_201211141845_1864939641.txt

hive> show tables

OK

查询MySQL数据库中的元数据~ mysql -uroot -p

mysql> use hive_metadata;

Database changed

mysql> show tables;

+-------------------------+

| Tables_in_hive_metadata |

+-------------------------+

| BUCKETING_COLS |

| CDS |

| COLUMNS_V2 |

| DATABASE_PARAMS |

| DBS |

| IDXS |

| INDEX_PARAMS |

| PARTITIONS |

| PARTITION_KEYS |

| PARTITION_KEY_VALS |

| PARTITION_PARAMS |

| PART_COL_PRIVS |

| PART_PRIVS |

| SDS |

| SD_PARAMS |

| SEQUENCE_TABLE |

| SERDES |

| SERDE_PARAMS |

| SORT_COLS |

| TABLE_PARAMS |

| TBLS |

| TBL_COL_PRIVS |

| TBL_PRIVS |

+-------------------------+

23 rows in set (0.00 sec)

Hive已经成功安装,下面是hive的使用攻略。

2. Hive的基本使用

1. 进入hive控制台~ cd /home/cos/toolkit/hive-0.9.0

~ bin/hive shell

Logging initialized using configuration in file:/home/cos/toolkit/hive-0.9.0/conf/hive-log4j.properties

Hive history file=/tmp/cos/hive_job_log_cos_201307160003_95040367.txt

hive>

新建表#创建数据(文本以tab分隔)

~ vi /home/cos/demo/t_hive.txt

16 2 3

61 12 13

41 2 31

17 21 3

71 2 31

1 12 34

11 2 34

#创建新表

hive> CREATE TABLE t_hive (a int, b int, c int) ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t';

OK

Time taken: 0.489 seconds

#导入数据t_hive.txt到t_hive表

hive> LOAD DATA LOCAL INPATH '/home/cos/demo/t_hive.txt' OVERWRITE INTO TABLE t_hive ;

Copying data from file:/home/cos/demo/t_hive.txt

Copying file: file:/home/cos/demo/t_hive.txt

Loading data to table default.t_hive

Deleted hdfs://c1.wtmart.com:9000/user/hive/warehouse/t_hive

OK

Time taken: 0.397 seconds

查看表和数据#查看表

hive> show tables;

OK

t_hive

Time taken: 0.099 seconds

#正则匹配表名

hive>show tables '*t*';

OK

t_hive

Time taken: 0.065 seconds

#查看表数据

hive> select * from t_hive;

OK

16 2 3

61 12 13

41 2 31

17 21 3

71 2 31

1 12 34

11 2 34

Time taken: 0.264 seconds

#查看表结构

hive> desc t_hive;

OK

a int

b int

c int

Time taken: 0.1 seconds

修改表#增加一个字段

hive> ALTER TABLE t_hive ADD COLUMNS (new_col String);

OK

Time taken: 0.186 seconds

hive> desc t_hive;

OK

a int

b int

c int

new_col string

Time taken: 0.086 seconds

#重命令表名

~ ALTER TABLE t_hive RENAME TO t_hadoop;

OK

Time taken: 0.45 seconds

hive> show tables;

OK

t_hadoop

Time taken: 0.07 seconds

删除表hive> DROP TABLE t_hadoop;

OK

Time taken: 0.767 seconds

hive> show tables;

OK

Time taken: 0.064 seconds

3. Hive交互式模式quit,exit:  退出交互式shell

reset: 重置配置为默认值

set =: 修改特定变量的值(如果变量名拼写错误,不会报错)

set :  输出用户覆盖的hive配置变量

set -v : 输出所有Hadoop和Hive的配置变量

add FILE[S] *, add JAR[S] *, add ARCHIVE[S] * : 添加 一个或多个 file, jar, archives到分布式缓存

list FILE[S], list JAR[S], list ARCHIVE[S] : 输出已经添加到分布式缓存的资源。

list FILE[S] *, list JAR[S] *,list ARCHIVE[S] * : 检查给定的资源是否添加到分布式缓存

delete FILE[S] *,delete JAR[S] *,delete ARCHIVE[S] * : 从分布式缓存删除指定的资源

! :  从Hive shell执行一个shell命令

dfs :  从Hive shell执行一个dfs命令

: 执行一个Hive 查询,然后输出结果到标准输出

source FILE :  在CLI里执行一个hive脚本文件

4. 数据导入

还以刚才的t_hive为例。#创建表结构

hive> CREATE TABLE t_hive (a int, b int, c int) ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t';

从操作本地文件系统加载数据(LOCAL)hive> LOAD DATA LOCAL INPATH '/home/cos/demo/t_hive.txt' OVERWRITE INTO TABLE t_hive ;

Copying data from file:/home/cos/demo/t_hive.txt

Copying file: file:/home/cos/demo/t_hive.txt

Loading data to table default.t_hive

Deleted hdfs://c1.wtmart.com:9000/user/hive/warehouse/t_hive

OK

Time taken: 0.612 seconds

#在HDFS中查找刚刚导入的数据

~ hadoop fs -cat /user/hive/warehouse/t_hive/t_hive.txt

16 2 3

61 12 13

41 2 31

17 21 3

71 2 31

1 12 34

11 2 34

从HDFS加载数据创建表t_hive2

hive> CREATE TABLE t_hive2 (a int, b int, c int) ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t';

#从HDFS加载数据

hive> LOAD DATA INPATH '/user/hive/warehouse/t_hive/t_hive.txt' OVERWRITE INTO TABLE t_hive2;

Loading data to table default.t_hive2

Deleted hdfs://c1.wtmart.com:9000/user/hive/warehouse/t_hive2

OK

Time taken: 0.325 seconds

#查看数据

hive> select * from t_hive2;

OK

16 2 3

61 12 13

41 2 31

17 21 3

71 2 31

1 12 34

11 2 34

Time taken: 0.287 seconds

从其他表导入数据hive> INSERT OVERWRITE TABLE t_hive2 SELECT * FROM t_hive ;

Total MapReduce jobs = 2

Launching Job 1 out of 2

Number of reduce tasks is set to 0 since there's no reduce operator

Starting Job = job_201307131407_0002, Tracking URL = http://c1.wtmart.com:50030/jobdetails.jsp?jobid=job_201307131407_0002

Kill Command = /home/cos/toolkit/hadoop-1.0.3/libexec/../bin/hadoop job -Dmapred.job.tracker=hdfs://c1.wtmart.com:9001 -kill job_201307131407_0002

Hadoop job information for Stage-1: number of mappers: 1; number of reducers: 0

2013-07-16 10:32:41,979 Stage-1 map = 0%, reduce = 0%

2013-07-16 10:32:48,034 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.03 sec

2013-07-16 10:32:49,050 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.03 sec

2013-07-16 10:32:50,068 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.03 sec

2013-07-16 10:32:51,082 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.03 sec

2013-07-16 10:32:52,093 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.03 sec

2013-07-16 10:32:53,102 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.03 sec

2013-07-16 10:32:54,112 Stage-1 map = 100%, reduce = 100%, Cumulative CPU 1.03 sec

MapReduce Total cumulative CPU time: 1 seconds 30 msec

Ended Job = job_201307131407_0002

Ended Job = -314818888, job is filtered out (removed at runtime).

Moving data to: hdfs://c1.wtmart.com:9000/tmp/hive-cos/hive_2013-07-16_10-32-31_323_5732404975764014154/-ext-10000

Loading data to table default.t_hive2

Deleted hdfs://c1.wtmart.com:9000/user/hive/warehouse/t_hive2

Table default.t_hive2 stats: [num_partitions: 0, num_files: 1, num_rows: 0, total_size: 56, raw_data_size: 0]

7 Rows loaded to t_hive2

MapReduce Jobs Launched:

Job 0: Map: 1 Cumulative CPU: 1.03 sec HDFS Read: 273 HDFS Write: 56 SUCCESS

Total MapReduce CPU Time Spent: 1 seconds 30 msec

OK

Time taken: 23.227 seconds

hive> select * from t_hive2;

OK

16 2 3

61 12 13

41 2 31

17 21 3

71 2 31

1 12 34

11 2 34

Time taken: 0.134 seconds

创建表并从其他表导入数据#删除表

hive> DROP TABLE t_hive;

#创建表并从其他表导入数据

hive> CREATE TABLE t_hive AS SELECT * FROM t_hive2 ;

Total MapReduce jobs = 2

Launching Job 1 out of 2

Number of reduce tasks is set to 0 since there's no reduce operator

Starting Job = job_201307131407_0003, Tracking URL = http://c1.wtmart.com:50030/jobdetails.jsp?jobid=job_201307131407_0003

Kill Command = /home/cos/toolkit/hadoop-1.0.3/libexec/../bin/hadoop job -Dmapred.job.tracker=hdfs://c1.wtmart.com:9001 -kill job_201307131407_0003

Hadoop job information for Stage-1: number of mappers: 1; number of reducers: 0

2013-07-16 10:36:48,612 Stage-1 map = 0%, reduce = 0%

2013-07-16 10:36:54,648 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.13 sec

2013-07-16 10:36:55,657 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.13 sec

2013-07-16 10:36:56,666 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.13 sec

2013-07-16 10:36:57,673 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.13 sec

2013-07-16 10:36:58,683 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 1.13 sec

2013-07-16 10:36:59,691 Stage-1 map = 100%, reduce = 100%, Cumulative CPU 1.13 sec

MapReduce Total cumulative CPU time: 1 seconds 130 msec

Ended Job = job_201307131407_0003

Ended Job = -670956236, job is filtered out (removed at runtime).

Moving data to: hdfs://c1.wtmart.com:9000/tmp/hive-cos/hive_2013-07-16_10-36-39_986_1343249562812540343/-ext-10001

Moving data to: hdfs://c1.wtmart.com:9000/user/hive/warehouse/t_hive

Table default.t_hive stats: [num_partitions: 0, num_files: 1, num_rows: 0, total_size: 56, raw_data_size: 0]

7 Rows loaded to hdfs://c1.wtmart.com:9000/tmp/hive-cos/hive_2013-07-16_10-36-39_986_1343249562812540343/-ext-10000

MapReduce Jobs Launched:

Job 0: Map: 1 Cumulative CPU: 1.13 sec HDFS Read: 272 HDFS Write: 56 SUCCESS

Total MapReduce CPU Time Spent: 1 seconds 130 msec

OK

Time taken: 20.13 seconds

hive> select * from t_hive;

OK

16 2 3

61 12 13

41 2 31

17 21 3

71 2 31

1 12 34

11 2 34

Time taken: 0.109 seconds

仅复制表结构不导数据hive> CREATE TABLE t_hive3 LIKE t_hive;

hive> select * from t_hive3;

OK

Time taken: 0.077 seconds

从MySQL数据库导入数据我们将在介绍Sqoop时讲。

5. 数据导出

从HDFS复制到HDFS其他位置~ hadoop fs -cp /user/hive/warehouse/t_hive /

~ hadoop fs -ls /t_hive

Found 1 items

-rw-r--r-- 1 cos supergroup 56 2013-07-16 10:41 /t_hive/000000_0

~ hadoop fs -cat /t_hive/000000_0

1623

611213

41231

17213

71231

11234

11234

通过Hive导出到本地文件系统hive> INSERT OVERWRITE LOCAL DIRECTORY '/tmp/t_hive' SELECT * FROM t_hive;

Total MapReduce jobs = 1

Launching Job 1 out of 1

Number of reduce tasks is set to 0 since there's no reduce operator

Starting Job = job_201307131407_0005, Tracking URL = http://c1.wtmart.com:50030/jobdetails.jsp?jobid=job_201307131407_0005

Kill Command = /home/cos/toolkit/hadoop-1.0.3/libexec/../bin/hadoop job -Dmapred.job.tracker=hdfs://c1.wtmart.com:9001 -kill job_201307131407_0005

Hadoop job information for Stage-1: number of mappers: 1; number of reducers: 0

2013-07-16 10:46:24,774 Stage-1 map = 0%, reduce = 0%

2013-07-16 10:46:30,823 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 0.87 sec

2013-07-16 10:46:31,833 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 0.87 sec

2013-07-16 10:46:32,844 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 0.87 sec

2013-07-16 10:46:33,856 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 0.87 sec

2013-07-16 10:46:34,865 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 0.87 sec

2013-07-16 10:46:35,873 Stage-1 map = 100%, reduce = 0%, Cumulative CPU 0.87 sec

2013-07-16 10:46:36,884 Stage-1 map = 100%, reduce = 100%, Cumulative CPU 0.87 sec

MapReduce Total cumulative CPU time: 870 msec

Ended Job = job_201307131407_0005

Copying data to local directory /tmp/t_hive

Copying data to local directory /tmp/t_hive

7 Rows loaded to /tmp/t_hive

MapReduce Jobs Launched:

Job 0: Map: 1 Cumulative CPU: 0.87 sec HDFS Read: 271 HDFS Write: 56 SUCCESS

Total MapReduce CPU Time Spent: 870 msec

OK

Time taken: 23.369 seconds

#查看本地操作系统

hive> ! cat /tmp/t_hive/000000_0;

hive> 1623

611213

41231

17213

71231

11234

11234

6. Hive查询HiveQL

注:以下代码将去掉map,reduce的日志输出部分。

普通查询:排序,列别名,嵌套子查询hive> FROM (

> SELECT b,c as c2 FROM t_hive

> ) t

> SELECT t.b, t.c2

> WHERE b>2

> LIMIT 2;

12 13

21 3

连接查询:JOINhive> SELECT t1.a,t1.b,t2.a,t2.b

> FROM t_hive t1 JOIN t_hive2 t2 on t1.a=t2.a

> WHERE t1.c>10;

1 12 1 12

11 2 11 2

41 2 41 2

61 12 61 12

71 2 71 2

聚合查询1:count, avghive> SELECT count(*), avg(a) FROM t_hive;

7 31.142857142857142

聚合查询2:count, distincthive> SELECT count(DISTINCT b) FROM t_hive;

3

聚合查询3:GROUP BY, HAVING#GROUP BY

hive> SELECT avg(a),b,sum(c) FROM t_hive GROUP BY b,c

16.0 2 3

56.0 2 62

11.0 2 34

61.0 12 13

1.0 12 34

17.0 21 3

#HAVING

hive> SELECT avg(a),b,sum(c) FROM t_hive GROUP BY b,c HAVING sum(c)>30

56.0 2 62

11.0 2 34

1.0 12 34

7. Hive视图

Hive视图和数据库视图的概念是一样的,我们还以t_hive为例。hive> CREATE VIEW v_hive AS SELECT a,b FROM t_hive where c>30;

hive> select * from v_hive;

41 2

71 2

1 12

11 2

删除视图hive> DROP VIEW IF EXISTS v_hive;

OK

Time taken: 0.495 seconds

8. Hive分区表

分区表是数据库的基本概念,但很多时候数据量不大,我们完全用不到分区表。Hive是一种OLAP数据仓库软件,涉及的数据量是非常大的,所以分区表在这个场景就显得非常重要!!

下面我们重新定义一个数据表结构:t_hft

创建数据~ vi /home/cos/demo/t_hft_20130627.csv

000001,092023,9.76

000002,091947,8.99

000004,092002,9.79

000005,091514,2.2

000001,092008,9.70

000001,092059,9.45

~ vi /home/cos/demo/t_hft_20130628.csv

000001,092023,9.76

000002,091947,8.99

000004,092002,9.79

000005,091514,2.2

000001,092008,9.70

000001,092059,9.45

创建数据表DROP TABLE IF EXISTS t_hft;

CREATE TABLE t_hft(

SecurityID STRING,

tradeTime STRING,

PreClosePx DOUBLE

) ROW FORMAT DELIMITED FIELDS TERMINATED BY ',';

创建分区数据表根据业务:按天和股票ID进行分区设计DROP TABLE IF EXISTS t_hft;

CREATE TABLE t_hft(

SecurityID STRING,

tradeTime STRING,

PreClosePx DOUBLE

) PARTITIONED BY (tradeDate INT)

ROW FORMAT DELIMITED FIELDS TERMINATED BY ',';

导入数据#20130627

hive> LOAD DATA LOCAL INPATH '/home/cos/demo/t_hft_20130627.csv' OVERWRITE INTO TABLE t_hft PARTITION (tradeDate=20130627);

Copying data from file:/home/cos/demo/t_hft_20130627.csv

Copying file: file:/home/cos/demo/t_hft_20130627.csv

Loading data to table default.t_hft partition (tradedate=20130627)

#20130628

hive> LOAD DATA LOCAL INPATH '/home/cos/demo/t_hft_20130628.csv' OVERWRITE INTO TABLE t_hft PARTITION (tradeDate=20130628);

Copying data from file:/home/cos/demo/t_hft_20130628.csv

Copying file: file:/home/cos/demo/t_hft_20130628.csv

Loading data to table default.t_hft partition (tradedate=20130628)

查看分区表hive> SHOW PARTITIONS t_hft;

tradedate=20130627

tradedate=20130628

Time taken: 0.082 seconds

查询数据hive> select * from t_hft where securityid='000001';

000001 092023 9.76 20130627

000001 092008 9.7 20130627

000001 092059 9.45 20130627

000001 092023 9.76 20130628

000001 092008 9.7 20130628

000001 092059 9.45 20130628

hive> select * from t_hft where tradedate=20130627 and PreClosePx<9;

000002 091947 8.99 20130627

000005 091514 2.2 20130627

Hive基于使用完成,这些都是日常的操作。后面我会继续讲一下,HiveQL优化及Hive的运维。

参照:http://blog.fens.me/hadoop-hive-intro/

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