hadoop中hive的属性
1.在hive中是可以删除文件的:
hive> dfs -rm -R /u2.txt > ; Deleted /u2.txt
2.hive 中的default数据库
<property> <name>hive.metastore.warehouse.dir</name> <value>/user/hive/warehouse</value> <description>location of default database for the warehouse</description> </property>
用default数据库创建表时,数据目录会在/user/hive/warehouse下
3.显示表头和默认数据库信息
hive> select * from u2; OK 1 xm1 16 9 14 2 xm2 18 9 14 3 xm3 22 9 14 4 xh4 20 9 14 5 xh5 22 9 14 6 xh6 23 9 14 7 xh7 25 9 14 8 xh8 28 9 14 9 xh9 32 9 14 Time taken: 0.999 seconds, Fetched: 9 row(s)
需要修改:hive-site.xml 默认的都是false,修改为true
<property> <name>hive.cli.print.header</name> <value>true</value> <description>Whether to print the names of the columns in query output.</description> </property> <property> <name>hive.cli.print.current.db</name> <value>true</value> <description>Whether to include the current database in the Hive prompt.</description> </property>
验证查询:
[hadoop@master sbin]$ hive Logging initialized using configuration in file:/home/hadoop/hive/conf/hive-log4j2.properties Async: true Hive-on-MR is deprecated in Hive 2 and may not be available in the future versions. Consider using a different execution engine (i.e. spark, tez) or using Hive 1.X releases. hive (default)> use db_hive; OK Time taken: 3.207 seconds hive (db_hive)> select * from u2; OK u2.id u2.name u2.age u2.month u2.day 1 xm1 16 9 14 2 xm2 18 9 14 3 xm3 22 9 14 4 xh4 20 9 14 5 xh5 22 9 14 6 xh6 23 9 14 7 xh7 25 9 14 8 xh8 28 9 14 9 xh9 32 9 14 Time taken: 1.254 seconds, Fetched: 9 row(s)
启动时配置信息:
$ bin/hive --hiveconf <property=value>
查看所有的设置信息:
hive>set -v;
查看一个属性值:
hive (db_hive)> set system:user.language ; system:user.language=en
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