HBase – Hadoop Database,是一个高可靠性、高性能、面向列、可伸缩的分布式存储系统,利用HBase技术可在廉价PC Server上搭建起大规模结构化存储集群。
HBase是Google Bigtable的开源实现,类似Google Bigtable利用GFS作为其文件存储系统,HBase利用Hadoop HDFS作为其文件存储系统;Google运行MapReduce来处理Bigtable中的海量数据,HBase同样利用Hadoop MapReduce来处理HBase中的海量数据;Google Bigtable利用 Chubby作为协同服务,HBase利用Zookeeper作为对应。
HBase常用命令
- 进入shell
[hadoop@indb-3-136-hzifc bin]$ echo $HBASE_HOME
/data/program/hbase
[hadoop@indb-3-136-hzifc bin]$ /data/program/hbase/bin/hbase shell
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/data/program/hbase-1.2.0-cdh5.8.3/lib/slf4j-log4j12-1.7.5.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/data/program/hadoop-2.6.0-cdh5.8.3/share/hadoop/common/lib/slf4j-log4j12-1.7.5.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [org.slf4j.impl.Log4jLoggerFactory]
HBase Shell; enter 'help<RETURN>' for list of supported commands.
Type "exit<RETURN>" to leave the HBase Shell
Version 1.2.0-cdh5.8.3, rUnknown, Wed Oct 12 20:33:08 PDT 2016
hbase(main):035:0> whoami
hadoop (auth:SIMPLE)
groups: hadoop
- 表结构
1. 创建表
语法:create <table>, {NAME => <family>, VERSIONS => <VERSIONS>}
创建一个User表,并且有一个info列族
hbase(main):002:0> create 'User','info'
0 row(s) in 1.5890 seconds
=> Hbase::Table - User
3. 查看所有表
hbase(main):003:0> list
TABLE
SYSTEM.CATALOG
SYSTEM.FUNCTION
SYSTEM.SEQUENCE
SYSTEM.STATS
TEST.USER
User
6 row(s) in 0.0340 seconds
=> ["SYSTEM.CATALOG", "SYSTEM.FUNCTION", "SYSTEM.SEQUENCE", "SYSTEM.STATS", "TEST.USER", "User"]
4. 查看表详情
hbase(main):004:0> describe 'User'
Table User is ENABLED
User
COLUMN FAMILIES DESCRIPTION
{NAME => 'info', BLOOMFILTER => 'ROW', VERSIONS => '1', IN_MEMORY => 'false', KEEP_DELETED_CELLS => 'FALSE', DATA_BLOCK_ENCODING => 'NONE', TTL => 'FORE
VER', COMPRESSION => 'NONE', MIN_VERSIONS => '0', BLOCKCACHE => 'true', BLOCKSIZE => '65536', REPLICATION_SCOPE => '0'}
1 row(s) in 0.1410 seconds
hbase(main):025:0> desc 'User'
Table User is ENABLED
User
COLUMN FAMILIES DESCRIPTION
{NAME => 'info', BLOOMFILTER => 'ROW', VERSIONS => '1', IN_MEMORY => 'false', KEEP_DELETED_CELLS => 'FALSE', DATA_BLOCK_ENCODING => 'NONE', TTL => 'FORE
VER', COMPRESSION => 'NONE', MIN_VERSIONS => '0', BLOCKCACHE => 'true', BLOCKSIZE => '65536', REPLICATION_SCOPE => '0'}
1 row(s) in 0.0380 seconds
5. 表修改
删除指定的列族
hbase(main):002:0> alter 'User', 'delete' => 'info'
Updating all regions with the new schema...
1/1 regions updated.
Done.
0 row(s) in 2.5340 seconds
- 表数据
1. 插入数据
语法:put <table>,<rowkey>,<family:column>,<value>
hbase(main):005:0> put 'User', 'row1', 'info:name', 'xiaoming'
0 row(s) in 0.1200 seconds
hbase(main):006:0> put 'User', 'row2', 'info:age', '18'
0 row(s) in 0.0170 seconds
hbase(main):007:0> put 'User', 'row3', 'info:sex', 'man'
0 row(s) in 0.0030 seconds
2. 根据rowKey查询某个记录
语法:get <table>,<rowkey>,[<family:column>,....]
hbase(main):008:0> get 'User', 'row2'
COLUMN CELL
info:age timestamp=1502368069926, value=18
1 row(s) in 0.0280 seconds
hbase(main):028:0> get 'User', 'row3', 'info:sex'
COLUMN CELL
info:sex timestamp=1502368093636, value=man
hbase(main):036:0> get 'User', 'row1', {COLUMN => 'info:name'}
COLUMN CELL
info:name timestamp=1502368030841, value=xiaoming
1 row(s) in 0.0120 seconds
3. 查询所有记录
语法:scan <table>, {COLUMNS => [ <family:column>,.... ], LIMIT => num}
扫描所有记录
hbase(main):009:0> scan 'User'
ROW COLUMN+CELL
row1 column=info:name, timestamp=1502368030841, value=xiaoming
row2 column=info:age, timestamp=1502368069926, value=18
row3 column=info:sex, timestamp=1502368093636, value=man
3 row(s) in 0.0380 seconds
扫描前2条
hbase(main):037:0> scan 'User', {LIMIT => 2}
ROW COLUMN+CELL
row1 column=info:name, timestamp=1502368030841, value=xiaoming
row2 column=info:age, timestamp=1502368069926, value=18
2 row(s) in 0.0170 seconds
范围查询
hbase(main):011:0> scan 'User', {STARTROW => 'row2'}
ROW COLUMN+CELL
row2 column=info:age, timestamp=1502368069926, value=18
row3 column=info:sex, timestamp=1502368093636, value=man
2 row(s) in 0.0170 seconds
hbase(main):012:0> scan 'User', {STARTROW => 'row2', ENDROW => 'row2'}
ROW COLUMN+CELL
row2 column=info:age, timestamp=1502368069926, value=18
1 row(s) in 0.0110 seconds
hbase(main):013:0> scan 'User', {STARTROW => 'row2', ENDROW => 'row3'}
ROW COLUMN+CELL
row2 column=info:age, timestamp=1502368069926, value=18
1 row(s) in 0.0120 seconds
另外,还可以添加TIMERANGE和FITLER等高级功能
STARTROW,ENDROW必须大写,否则报错;查询结果不包含等于ENDROW的结果集
4. 统计表记录数
语法:count <table>, {INTERVAL => intervalNum, CACHE => cacheNum}
INTERVAL设置多少行显示一次及对应的rowkey,默认1000;CACHE每次去取的缓存区大小,默认是10,调整该参数可提高查询速度
hbase(main):020:0> count 'User'
3 row(s) in 0.0360 seconds
=> 3
5. 删除
删除列
hbase(main):008:0> delete 'User', 'row1', 'info:age'
0 row(s) in 0.0290 seconds
删除所有行
hbase(main):014:0> deleteall 'User', 'row2'
0 row(s) in 0.0090 seconds
删除表中所有数据
hbase(main):016:0> truncate 'User'
Truncating 'User' table (it may take a while):
- Disabling table...
- Truncating table...
0 row(s) in 3.6610 seconds
- 表管理
1. 禁用表
hbase(main):014:0> disable 'User'
0 row(s) in 2.2660 seconds
hbase(main):015:0> describe 'User'
Table User is DISABLED
User
COLUMN FAMILIES DESCRIPTION
{NAME => 'info', BLOOMFILTER => 'ROW', VERSIONS => '1', IN_MEMORY => 'false', KEEP_DELETED_CELLS => 'FALSE', DATA_BLOCK_ENCODING => 'NONE', TTL => 'FORE
VER', COMPRESSION => 'NONE', MIN_VERSIONS => '0', BLOCKCACHE => 'true', BLOCKSIZE => '65536', REPLICATION_SCOPE => '0'}
1 row(s) in 0.0340 seconds
hbase(main):016:0> scan 'User', {STARTROW => 'row2', ENDROW => 'row3'}
ROW COLUMN+CELL
ERROR: User is disabled.
2. 启用表
hbase(main):017:0> enable 'User'
0 row(s) in 1.3470 seconds
hbase(main):018:0> describe 'User'
Table User is ENABLED
User
COLUMN FAMILIES DESCRIPTION
{NAME => 'info', BLOOMFILTER => 'ROW', VERSIONS => '1', IN_MEMORY => 'false', KEEP_DELETED_CELLS => 'FALSE', DATA_BLOCK_ENCODING => 'NONE', TTL => 'FORE
VER', COMPRESSION => 'NONE', MIN_VERSIONS => '0', BLOCKCACHE => 'true', BLOCKSIZE => '65536', REPLICATION_SCOPE => '0'}
1 row(s) in 0.0310 seconds
hbase(main):019:0> scan 'User', {STARTROW => 'row2', ENDROW => 'row3'}
ROW COLUMN+CELL
row2 column=info:age, timestamp=1502368069926, value=18
1 row(s) in 0.0280 seconds
3. 测试表是否存在
hbase(main):022:0> exists 'User'
Table User does exist
0 row(s) in 0.0150 seconds
hbase(main):023:0> exists 'user'
Table user does not exist
0 row(s) in 0.0110 seconds
hbase(main):024:0> exists user
NameError: undefined local variable or method `user' for #<Object:0x412ebe64>
4. 删除表
删除前,必须先disable
hbase(main):030:0> drop 'TEST.USER'
ERROR: Table TEST.USER is enabled. Disable it first.
Here is some help for this command:
Drop the named table. Table must first be disabled:
hbase> drop 't1'
hbase> drop 'ns1:t1'
hbase(main):031:0> disable 'TEST.USER'
0 row(s) in 2.2640 seconds
hbase(main):033:0> drop 'TEST.USER'
0 row(s) in 1.2490 seconds
hbase(main):034:0> list
TABLE
SYSTEM.CATALOG
SYSTEM.FUNCTION
SYSTEM.SEQUENCE
SYSTEM.STATS
User
5 row(s) in 0.0080 seconds
=> ["SYSTEM.CATALOG", "SYSTEM.FUNCTION", "SYSTEM.SEQUENCE", "SYSTEM.STATS", "User"]