HBase基本操作
使用HBase shell进入HBase命令行,之后在hbase命令提示符下:
1.help查看所有支持的命令2.直接输入命令,可以查看该命令的使用方法,如hbase(main):018:0>create3 .创建表:create ‘wxy:test’, 'cf' (wxy为表空间,test为表名,cf为列族的名称)create ‘wxy:test’, {NAME=>'cf', VERSION=>3}, {NAME=>'cf2'},4.查看所有的表:list5.查看表结构: descibe ‘wxy:test’6.增加/删除一个列族:disable 'wxy:test'alter 'wxy:test','cf2'enable 'wxy:test'disable 'wxy:test'alter 'wxy:test',{NAME=>'cf2',METHOD=>'delete'}enable 'wxy:test'7.修改表的结构:
- 对列族的修改跟创建时类似(参看alter的帮助:Column families work in a similar way as the 'create' command)
alter 'wxy:test',{NAME => 'cf',VERSIONS => 2} #--对列族cf增加对历史版本的支持alter 'wxy:test',{NAME => 'f1', VERSIONS => 5} #--创建新的列族f1alter 'wxy:test, {}NAME => 'f1', METHOD => 'delete' } #--删除列族f18.查看一个表是否存在: exists ‘wxy:test’9.查看表是否可以修改:is_enabled 'wxy:test'10.删除某张表: disable 'wxy:test'drop 'wxy:test'enable 'wxy:test'11.向表中插入/更新数据:put 'wxy:test','rk1','cf:name','zhangsan' #--列可以事先不存在,直接put即可,update数据也 #是put,只要行健和列相同即可put 'wxy:test','rk1','cf:sex','female'put 'wxy:test','rk1','cf:name','zhangsan2' #-更新数据put 'wxy:test','rk1','cf:name','zhangsan3' #-更新数据put 'wxy:test','rk1','cf:name','zhangsan4' #-更新数据12.删除表中数据:delete 'wxy:test','rk1'delete 'wxy:test','rk1','cf'13.get获取数据:(通过rowkey访问)get 'wxy:test','rk1'get 'wxy:test','rk1','cf'get 'wxy:test','rk1','cf','cf2'get 'wxy:test','rk1','cf:name'14.scan获取表的数据(可以不通过rowkey访问):scan 'wxy:test'scan 'wxy:test',{LIMIT=>3}scan 'wxy:test',{STARTROW=>'rk1',LIMIT=>3}scan 'wxy:test',{COLUMNS=>'cf:name'}默认情况下用scan获取只能获取最新数据,如果想看历史数据,需要打开RAW属性{RAW=>TRUE}scan 'wxy:test',{RAW=>true,VERSIONS=>3}15.统计表的行数: count 'wxy:test'16.清空表:truncate 'wxy:test'