Hbase is installed on the top of the Hadoop and it uses the Hadoop file system only. Just like other Bigdata framework such as Hive, Pig etc, Hbase provides jruby interactive shell. You can also use the Java API to interact with Hbase. In this article, we will check some commonly used HBase table management shell commands and explanation on how to use them.
Commonly used HBase Table Management Shell Commands
In HBase, jruby interactive shell mode is used to interact with HBase for table operations, table management, and data modeling. We will check out HBase Table Management shell commands.
The commonly used HBase table management shell commands are: List, Create, Describe, Disable, Disable_all, Enable,Enable_all, Drop, Drop_all, Show_filters, Alter, Alter_status.
HBase List Command
The HBase list command will display the list of the table present in the HBase, It will show the all tables including one present in different namespace.
Below is the example of the list command:
hbase(main):051:0> list TABLE emp emp1 my_ns:test personal test:test1 5 row(s) in 0.0080 seconds => ["SYSTEM.CATALOG", "SYSTEM.FUNCTION", "SYSTEM.SEQUENCE", "SYSTEM.STATS", "emp", "emp1", "my_ns:test", "personal, "test:test1"]
HBase Create Command
Create command is used to create a table in the HBase.
Read:
- HBase Exit Code – Capture Last Executed Command Status
- HBase Create Table Shell command and Examples
HBase Describe Command
This command describes the named given table. It will give more information about columns and column families present in the given table. This command also display the various attributes such as VERSIONS, TTL etc.
HBase Describe Example
Below is the example of HBase describe the table which we have created:
hbase(main):053:0> describe 'test'
Table test is ENABLED
test
COLUMN FAMILIES DESCRIPTION
{NAME => 'colF', BLOOMFILTER => 'ROW', VERSIONS => '1', IN_MEMORY => 'false', KEEP_DELETED_CELLS => 'FALSE', DATA_BLOCK_ENCODING => 'NONE', TTL => 'FOREVER', COMPRESSIO
N => 'NONE', MIN_VERSIONS => '0', BLOCKCACHE => 'true', BLOCKSIZE => '65536', REPLICATION_SCOPE => '0'}
1 row(s) in 0.1380 seconds
HBase is_enabled Command
This command is used to verify the named tables is enable or disabled.
HBase is_enabled Command Example
Below is example to demonstrate is_enabled command:
hbase(main):061:0> is_enabled 'test' true 0 row(s) in 0.0200 seconds
HBase disable and disable_all Command
It is mandatory to disable table if you want to delete or drop it. HBase disable table command disable the named table. Use disable_all command to disable all tables that matches the regular expression.
HBase disable and disable_all Syntax
Below is the syntax of HBase disable and disable_all command:
disable <table name> disable_all <RegExp>
HBase disable and disable_all Command Example
Below is the example to demonstrate disable and disable_all
hbase(main):054:0> disable 'test' 0 row(s) in 2.4540 seconds hbase(main):057:0> disable_all 'test.*' test test:test1 Disable the above 2 tables (y/n)? y 2 tables successfully disabled
HBase enable and enable_all Command
HBase enable and enable_all command is used to enable the named table(s). Use enable_all command to enable all tables that matches the regular expression.
HBase enable and enable_all Syntax
Below is the syntax of HBase enable and enable_all command:
enable <table name> enable_all <RegExp>
HBase disable and disable_all Command Example
Below is the example to demonstrate disable and disable_all commands.
hbase(main):055:0> enable 'test' 0 row(s) in 1.2860 seconds hbase(main):058:0> enable_all 'test.*' test test:test1 Enable the above 2 tables (y/n)? y 2 tables successfully enabled
HBase drop and drop_all Command
This command is used to drop the named table. Drop_all command drops all tables that matched regular expression.
Read: HBase drop table command and Examples
HBase show_filters Command
This command is used to displays all the filters present in HBase such as ColumnPrefix Filter, TimestampsFilter, PageFilter, FamilyFilter, etc.
Below is the example to use show_filters:
hbase(main):059:0> show_filters DependentColumnFilter KeyOnlyFilter ColumnCountGetFilter SingleColumnValueFilter PrefixFilter SingleColumnValueExcludeFilter FirstKeyOnlyFilter ColumnRangeFilter TimestampsFilter FamilyFilter QualifierFilter ColumnPrefixFilter RowFilter MultipleColumnPrefixFilter InclusiveStopFilter PageFilter ValueFilter ColumnPaginationFilter
HBase alter Command and Examples
This command is used to alter the named table.
Read:
HBase Alter_status Command
You can use this command to can get the status of the alter command. Which indicates the number of regions of the table that have received the updated schema pass table name.
BHase alter_status command Example
Below is the example to use alter_status command:
hbase(main):060:0> alter_status 'test' 1/1 regions updated. Done.