HBase shell commands
As told in HBase introduction, HBase provides Extensible jruby-based (JIRB) shell as a feature to execute some commands(each command represents one functionality).
HBase shell commands are mainly categorized into 6 parts
1) General HBase shell commands
| status | Show cluster status. Can be ‘summary’, ‘simple’, or ‘detailed’. Thedefault is ‘summary’.hbase> status****hbase> status ‘simple’****hbase> status ‘summary’****hbase> status ‘detailed’ |
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| version | Output this HBase versionUsage:****hbase> version |
| whoami | Show the current hbase user.Usage:****hbase> whoami |
2) Tables Management commands
| alter | Alter column family schema; pass table name and a dictionaryspecifying new column family schema. Dictionaries are describedon the main help command output. Dictionary must include nameof column family to alter.For example, to change or add the ‘f1’ column family in table ‘t1’ fromcurrent value to keep a maximum of 5 cell VERSIONS, do:hbase> alter ‘t1’, NAME => ‘f1’, VERSIONS => 5You can operate on several column families:hbase> alter ‘t1’, ‘f1’, {NAME => ‘f2’, IN_MEMORY => true}, {NAME => ‘f3’, VERSIONS => 5}To delete the ‘f1’ column family in table ‘t1’, use one of:hbase> alter ‘t1’, NAME => ‘f1’, METHOD => ‘delete’hbase> alter ‘t1’, ‘delete’ => ‘f1’You can also change table-scope attributes like MAX_FILESIZE, READONLY,MEMSTORE_FLUSHSIZE, DEFERRED_LOG_FLUSH, etc. These can be put at the end;for example, to change the max size of a region to 128MB, do:hbase> alter ‘t1’, MAX_FILESIZE => ‘134217728’You can add a table coprocessor by setting a table coprocessor attribute:hbase> alter ‘t1’,****‘coprocessor’=>’hdfs:///foo.jar|com.foo.FooRegionObserver|1001|arg1=1,arg2=2’Since you can have multiple coprocessors configured for a table, asequence number will be automatically appended to the attribute nameto uniquely identify it.The coprocessor attribute must match the pattern below in order forthe framework to understand how to load the coprocessor classes:[coprocessor jar file location] | class name | [priority] | [arguments]You can also set configuration settings specific to this table or column family:hbase> alter ‘t1’, CONFIGURATION => {‘hbase.hregion.scan.loadColumnFamiliesOnDemand’ => ‘true’}****hbase> alter ‘t1’, {NAME => ‘f2’, CONFIGURATION => {‘hbase.hstore.blockingStoreFiles’ => ’10’}}You can also remove a table-scope attribute:hbase> alter ‘t1’, METHOD => ‘table_att_unset’, NAME => ‘MAX_FILESIZE’****hbase> alter ‘t1’, METHOD => ‘table_att_unset’, NAME => ‘coprocessor$1’There could be more than one alteration in one command:hbase> alter ‘t1’, { NAME => ‘f1’, VERSIONS => 3 },****{ MAX_FILESIZE => ‘134217728’ }, { METHOD => ‘delete’, NAME => ‘f2’ },****OWNER => ‘johndoe’, METADATA => { ‘mykey’ => ‘myvalue’ } |
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| create | Create table; pass table name, a dictionary of specifications percolumn family, and optionally a dictionary of table configuration.hbase> create ‘t1’, {NAME => ‘f1’, VERSIONS => 5}****hbase> create ‘t1’, {NAME => ‘f1’}, {NAME => ‘f2’}, {NAME => ‘f3’}****hbase> # The above in shorthand would be the following:****hbase> create ‘t1’, ‘f1’, ‘f2’, ‘f3’****hbase> create ‘t1’, {NAME => ‘f1’, VERSIONS => 1, TTL => 2592000, BLOCKCACHE => true}****hbase> create ‘t1’, {NAME => ‘f1’, CONFIGURATION => {‘hbase.hstore.blockingStoreFiles’ => ’10’}}Table configuration options can be put at the end. |
| describe | Describe the named table.hbase> describe ‘t1’ |
| disable | Start disable of named tablehbase> disable ‘t1’ |
| disable_all | Disable all of tables matching the given regexhbase> disable_all ‘t.*’ |
| is_disabled | verifies Is named table disabledhbase> is_disabled ‘t1’ |
| drop | Drop the named table. Table must first be disabledhbase> drop ‘t1’ |
| drop_all | Drop all of the tables matching the given regexhbase> drop_all ‘t.*’ |
| enable | Start enable of named tablehbase> enable ‘t1’ |
| enable_all | Enable all of the tables matching the given regexhbase> enable_all ‘t.*’ |
| is_enabled | verifies Is named table enabledhbase> is_enabled ‘t1’ |
| exists | Does the named table existhbase> exists ‘t1’ |
| list | List all tables in hbase. Optional regular expression parameter couldbe used to filter the outputhbase> list****hbase> list ‘abc.*’ |
| show_filters | Show all the filters in hbase.hbase> show_filters |
| alter_status | Get the status of the alter command. Indicates the number of regions of the table that have received the updated schema Pass table name.hbase> alter_status ‘t1’ |
| alter_async | Alter column family schema, does not wait for all regions to receive theschema changes. Pass table name and a dictionary specifying new columnfamily schema. Dictionaries are described on the main help command output.Dictionary must include name of column family to alter.To change or add the ‘f1’ column family in table ‘t1’ from defaultsto instead keep a maximum of 5 cell VERSIONS, do:hbase> alter_async ‘t1’, NAME => ‘f1’, VERSIONS => 5To delete the ‘f1’ column family in table ‘t1’, do:hbase> alter_async ‘t1’, NAME => ‘f1’, METHOD => ‘delete’or a shorter version:hbase> alter_async ‘t1’, ‘delete’ => ‘f1’You can also change table-scope attributes like MAX_FILESIZEMEMSTORE_FLUSHSIZE, READONLY, and DEFERRED_LOG_FLUSH.For example, to change the max size of a family to 128MB, do:hbase> alter ‘t1’, METHOD => ‘table_att’, MAX_FILESIZE => ‘134217728’There could be more than one alteration in one command:hbase> alter ‘t1’, {NAME => ‘f1’}, {NAME => ‘f2’, METHOD => ‘delete’}To check if all the regions have been updated, use alter_status <table_name> |
3) Data Manipulation commands
| count | Count the number of rows in a table. Return value is the number of rows.This operation may take a LONG time (Run ‘$HADOOP_HOME/bin/hadoop jarhbase.jar rowcount’ to run a counting mapreduce job). Current count is shownevery 1000 rows by default. Count interval may be optionally specified. Scancaching is enabled on count scans by default. Default cache size is 10 rows.If your rows are small in size, you may want to increase thisparameter. Examples:hbase> count ‘t1’hbase> count ‘t1’, INTERVAL => 100000****hbase> count ‘t1’, CACHE => 1000****hbase> count ‘t1’, INTERVAL => 10, CACHE => 1000The same commands also can be run on a table reference. Suppose you had a referencet to table ‘t1’, the corresponding commands would be:hbase> t.counthbase> t.count INTERVAL => 100000****hbase> t.count CACHE => 1000****hbase> t.count INTERVAL => 10, CACHE => 1000 |
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| delete | Put a delete cell value at specified table/row/column and optionallytimestamp coordinates. Deletes must match the deleted cell’scoordinates exactly. When scanning, a delete cell suppresses olderversions. To delete a cell from ‘t1’ at row ‘r1’ under column ‘c1’marked with the time ‘ts1’, do:hbase> delete ‘t1’, ‘r1’, ‘c1’, ts1The same command can also be run on a table reference. Suppose you had a referencet to table ‘t1’, the corresponding command would be:hbase> t.delete ‘r1’, ‘c1’, ts1 |
| deleteall | Delete all cells in a given row; pass a table name, row, and optionallya column and timestamp. Examples:hbase> deleteall ‘t1’, ‘r1’hbase> deleteall ‘t1’, ‘r1’, ‘c1’****hbase> deleteall ‘t1’, ‘r1’, ‘c1’, ts1The same commands also can be run on a table reference. Suppose you had a referencet to table ‘t1’, the corresponding command would be:hbase> t.deleteall ‘r1’hbase> t.deleteall ‘r1’, ‘c1’****hbase> t.deleteall ‘r1’, ‘c1’, ts1 |
| get | Get row or cell contents; pass table name, row, and optionallya dictionary of column(s), timestamp, timerange and versions. Examples:hbase> get ‘t1’, ‘r1’****hbase> get ‘t1’, ‘r1’, {TIMERANGE => [ts1, ts2]}****hbase> get ‘t1’, ‘r1’, {COLUMN => ‘c1’}****hbase> get ‘t1’, ‘r1’, {COLUMN => [‘c1’, ‘c2’, ‘c3’]}****hbase> get ‘t1’, ‘r1’, {COLUMN => ‘c1’, TIMESTAMP => ts1}****hbase> get ‘t1’, ‘r1’, {COLUMN => ‘c1’, TIMERANGE => [ts1, ts2], VERSIONS => 4}****hbase> get ‘t1’, ‘r1’, {COLUMN => ‘c1’, TIMESTAMP => ts1, VERSIONS => 4}****hbase> get ‘t1’, ‘r1’, {FILTER => “ValueFilter(=, ‘binary:abc’)”}****hbase> get ‘t1’, ‘r1’, ‘c1’****hbase> get ‘t1’, ‘r1’, ‘c1’, ‘c2’****hbase> get ‘t1’, ‘r1’, [‘c1’, ‘c2’]Besides the default ‘toStringBinary’ format, ‘get’ also supports custom formatting bycolumn. A user can define a FORMATTER by adding it to the column name in the getspecification. The FORMATTER can be stipulated:1. either as a org.apache.hadoop.hbase.util.Bytes method name (e.g, toInt, toString)2. or as a custom class followed by method name: e.g. ‘c(MyFormatterClass).format’.Example formatting cf:qualifier1 and cf:qualifier2 both as Integers:hbase> get ‘t1’, ‘r1’ {COLUMN => [‘cf:qualifier1:toInt’,‘cf:qualifier2:c(org.apache.hadoop.hbase.util.Bytes).toInt’] }Note that you can specify a FORMATTER by column only (cf:qualifer). You cannot specifya FORMATTER for all columns of a column family.The same commands also can be run on a reference to a table (obtained via get_table orcreate_table). Suppose you had a reference t to table ‘t1’, the corresponding commandswould be:hbase> t.get ‘r1’****hbase> t.get ‘r1’, {TIMERANGE => [ts1, ts2]}****hbase> t.get ‘r1’, {COLUMN => ‘c1’}****hbase> t.get ‘r1’, {COLUMN => [‘c1’, ‘c2’, ‘c3’]}****hbase> t.get ‘r1’, {COLUMN => ‘c1’, TIMESTAMP => ts1}****hbase> t.get ‘r1’, {COLUMN => ‘c1’, TIMERANGE => [ts1, ts2], VERSIONS => 4}****hbase> t.get ‘r1’, {COLUMN => ‘c1’, TIMESTAMP => ts1, VERSIONS => 4}****hbase> t.get ‘r1’, {FILTER => “ValueFilter(=, ‘binary:abc’)”}****hbase> t.get ‘r1’, ‘c1’****hbase> t.get ‘r1’, ‘c1’, ‘c2’****hbase> t.get ‘r1’, [‘c1’, ‘c2’] |
| get_counter | Return a counter cell value at specified table/row/column coordinates.A cell cell should be managed with atomic increment function oh HBaseand the data should be binary encoded. Example:hbase> get_counter ‘t1’, ‘r1’, ‘c1’The same commands also can be run on a table reference. Suppose you had a referencet to table ‘t1’, the corresponding command would be:hbase> t.get_counter ‘r1’, ‘c1’ |
| incr | Increments a cell ‘value’ at specified table/row/column coordinates.To increment a cell value in table ‘t1’ at row ‘r1’ under column‘c1’ by 1 (can be omitted) or 10 do:hbase> incr ‘t1’, ‘r1’, ‘c1’****hbase> incr ‘t1’, ‘r1’, ‘c1’, 1****hbase> incr ‘t1’, ‘r1’, ‘c1’, 10The same commands also can be run on a table reference. Suppose you had a referencet to table ‘t1’, the corresponding command would be:hbase> t.incr ‘r1’, ‘c1’hbase> t.incr ‘r1’, ‘c1’, 1****hbase> t.incr ‘r1’, ‘c1’, 10 |
| put | Put a cell ‘value’ at specified table/row/column and optionallytimestamp coordinates. To put a cell value into table ‘t1’ atrow ‘r1’ under column ‘c1’ marked with the time ‘ts1’, do:hbase> put ‘t1’, ‘r1’, ‘c1’, ‘value’, ts1The same commands also can be run on a table reference. Suppose you had a referencet to table ‘t1’, the corresponding command would be:hbase> t.put ‘r1’, ‘c1’, ‘value’, ts1 |
| scan | Scan a table; pass table name and optionally a dictionary of scannerspecifications. Scanner specifications may include one or more of:TIMERANGE, FILTER, LIMIT, STARTROW, STOPROW, TIMESTAMP, MAXLENGTH,or COLUMNS, CACHEIf no columns are specified, all columns will be scanned.To scan all members of a column family, leave the qualifier empty as in‘col_family:’.The filter can be specified in two ways:1. Using a filterString – more information on this is available in theFilter Language document attached to the HBASE-4176 JIRA2. Using the entire package name of the filter.Some examples:hbase> scan ‘.META.’hbase> scan ‘.META.’, {COLUMNS => ‘info:regioninfo’}****hbase> scan ‘t1’, {COLUMNS => [‘c1’, ‘c2’], LIMIT => 10, STARTROW => ‘xyz’}****hbase> scan ‘t1’, {COLUMNS => ‘c1’, TIMERANGE => [1303668804, 1303668904]}****hbase> scan ‘t1’, {FILTER => “(PrefixFilter (‘row2’) AND****(QualifierFilter (>=, ‘binary:xyz’))) AND (TimestampsFilter ( 123, 456))”}****hbase> scan ‘t1’, {FILTER =>****org.apache.hadoop.hbase.filter.ColumnPaginationFilter.new(1, 0)}For experts, there is an additional option — CACHE_BLOCKS — whichswitches block caching for the scanner on (true) or off (false). Bydefault it is enabled. Examples:hbase> scan ‘t1’, {COLUMNS => [‘c1’, ‘c2’], CACHE_BLOCKS => false}Also for experts, there is an advanced option — RAW — which instructs thescanner to return all cells (including delete markers and uncollected deletedcells). This option cannot be combined with requesting specific COLUMNS.Disabled by default. Example:hbase> scan ‘t1’, {RAW => true, VERSIONS => 10}Besides the default ‘toStringBinary’ format, ‘scan’ supports custom formattingby column. A user can define a FORMATTER by adding it to the column name inthe scan specification. The FORMATTER can be stipulated:1. either as a org.apache.hadoop.hbase.util.Bytes method name (e.g, toInt, toString)2. or as a custom class followed by method name: e.g. ‘c(MyFormatterClass).format’.Example formatting cf:qualifier1 and cf:qualifier2 both as Integers:hbase> scan ‘t1’, {COLUMNS => [‘cf:qualifier1:toInt’,‘cf:qualifier2:c(org.apache.hadoop.hbase.util.Bytes).toInt’] }Note that you can specify a FORMATTER by column only (cf:qualifer). You cannotspecify a FORMATTER for all columns of a column family.Scan can also be used directly from a table, by first getting a reference to atable, like such:hbase> t = get_table ‘t’****hbase> t.scanNote in the above situation, you can still provide all the filtering, columns,options, etc as described above. |
| truncate | Disables, drops and recreates the specified table.Examples:hbase>truncate ‘t1’ |
4) HBase surgery tools
| assign | Assign a region. Use with caution. If region already assigned,this command will do a force reassign. For experts only.Examples:hbase> assign ‘REGION_NAME’ |
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| balancer | Trigger the cluster balancer. Returns true if balancer ran and was able totell the region servers to unassign all the regions to balance (the re-assignment itself is async).Otherwise false (Will not run if regions in transition).Examples:hbase> balancer |
| balance_switch | Enable/Disable balancer. Returns previous balancer state.Examples:hbase> balance_switch true****hbase> balance_switch false |
| close_region | Close a single region. Ask the master to close a region out on the clusteror if ‘SERVER_NAME’ is supplied, ask the designated hosting regionserver toclose the region directly. Closing a region, the master expects ‘REGIONNAME’to be a fully qualified region name. When asking the hosting regionserver todirectly close a region, you pass the regions’ encoded name only. A regionname looks like this:TestTable,0094429456,1289497600452.527db22f95c8a9e0116f0cc13c680396.The trailing period is part of the regionserver name. A region’s encoded nameis the hash at the end of a region name; e.g. 527db22f95c8a9e0116f0cc13c680396(without the period). A ‘SERVER_NAME’ is its host, port plus startcode. Forexample: host187.example.com,60020,1289493121758 (find servername in master uior when you do detailed status in shell). This command will end up runningclose on the region hosting regionserver. The close is done without themaster’s involvement (It will not know of the close). Once closed, region willstay closed. Use assign to reopen/reassign. Use unassign or move to assignthe region elsewhere on cluster. Use with caution. For experts only.Examples:hbase> close_region ‘REGIONNAME’hbase> close_region ‘REGIONNAME’, ‘SERVER_NAME’ |
| compact | Compact all regions in passed table or pass a region rowto compact an individual region. You can also compact a single columnfamily within a region.Examples:Compact all regions in a table:hbase> compact ‘t1’Compact an entire region:hbase> compact ‘r1’Compact only a column family within a region:hbase> compact ‘r1’, ‘c1’Compact a column family within a table:hbase> compact ‘t1’, ‘c1’ |
| flush | Flush all regions in passed table or pass a region row toflush an individual region. For example:hbase> flush ‘TABLENAME’hbase> flush ‘REGIONNAME’ |
| major_compact | Run major compaction on passed table or pass a region rowto major compact an individual region. To compact a singlecolumn family within a region specify the region namefollowed by the column family name.Examples:Compact all regions in a table:hbase> major_compact ‘t1’Compact an entire region:hbase> major_compact ‘r1’Compact a single column family within a region:hbase> major_compact ‘r1’, ‘c1’Compact a single column family within a table:hbase> major_compact ‘t1’, ‘c1’ |
| move | Move a region. Optionally specify target regionserver else we choose oneat random. NOTE: You pass the encoded region name, not the region name sothis command is a little different to the others. The encoded region nameis the hash suffix on region names: e.g. if the region name wereTestTable,0094429456,1289497600452.527db22f95c8a9e0116f0cc13c680396. thenthe encoded region name portion is 527db22f95c8a9e0116f0cc13c680396A server name is its host, port plus startcode. For example:host187.example.com,60020,1289493121758Examples:hbase> move ‘ENCODED_REGIONNAME’hbase> move ‘ENCODED_REGIONNAME’, ‘SERVER_NAME’ |
| split | Split entire table or pass a region to split individual region. With thesecond parameter, you can specify an explicit split key for the region.Examples:split ‘tableName’****split ‘regionName’ # format: ‘tableName,startKey,id’****split ‘tableName’, ‘splitKey’****split ‘regionName’, ‘splitKey’ |
| unassign | Unassign a region. Unassign will close region in current location and thenreopen it again. Pass ‘true’ to force the unassignment (‘force’ will clearall in-memory state in master before the reassign. If results indouble assignment use hbck -fix to resolve. To be used by experts).Use with caution. For expert use only. Examples:hbase> unassign ‘REGIONNAME’hbase> unassign ‘REGIONNAME’, true |
| hlog_roll | Roll the log writer. That is, start writing log messages to a new file.The name of the regionserver should be given as the parameter. A‘server_name’ is the host, port plus startcode of a regionserver. Forexample: host187.example.com,60020,1289493121758 (find servername inmaster ui or when you do detailed status in shell)hbase>hlog_roll |
| zk_dump | Dump status of HBase cluster as seen by ZooKeeper. Example:hbase>zk_dump |
5) Cluster replication tools
| add_peer | Add a peer cluster to replicate to, the id must be a short andthe cluster key is composed like this:hbase.zookeeper.quorum:hbase.zookeeper.property.clientPort:zookeeper.znode.parentThis gives a full path for HBase to connect to another cluster.Examples:hbase> add_peer ‘1’, “server1.cie.com:2181:/hbase”hbase> add_peer ‘2’, “zk1,zk2,zk3:2182:/hbase-prod” |
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| remove_peer | Stops the specified replication stream and deletes all the metainformation kept about it. Examples:hbase> remove_peer ‘1’ |
| list_peers | List all replication peer clusters.hbase> list_peers |
| enable_peer | Restarts the replication to the specified peer cluster,continuing from where it was disabled.Examples:hbase> enable_peer ‘1’ |
| disable_peer | Stops the replication stream to the specified cluster, but stillkeeps track of new edits to replicate.Examples:hbase> disable_peer ‘1’ |
| start_replication | Restarts all the replication features. The state in which eachstream starts in is undetermined.WARNING:start/stop replication is only meant to be used in critical load situations.Examples:hbase> start_replication |
| stop_replication | Stops all the replication features. The state in which eachstream stops in is undetermined.WARNING:start/stop replication is only meant to be used in critical load situations.Examples:hbase> stop_replication |
6) Security tools
| grant | Grant users specific rights.Syntax : grantpermissions is either zero or more letters from the set “RWXCA”.READ(‘R’), WRITE(‘W’), EXEC(‘X’), CREATE(‘C’), ADMIN(‘A’)For example:hbase> grant ‘bobsmith’, ‘RWXCA’hbase> grant ‘bobsmith’, ‘RW’, ‘t1’, ‘f1’, ‘col1’ |
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| revoke | Revoke a user’s access rights.Syntax : revokeFor example:hbase> revoke ‘bobsmith’, ‘t1’, ‘f1’, ‘col1’ |
| user_permission | Show all permissions for the particular user.Syntax : user_permissionFor example:hbase> user_permissionhbase> user_permission ‘table1’ |
https://learnhbase.wordpress.com/2013/03/02/hbase-shell-commands/
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