HBase Tutorial (ii) HBase database Shell command

HBase Tutorial (ii) HBase database Shell command

1 Hbase-shell Command

HBase is a distributed, column-oriented open source database, HBase also provides the shell command of the database to add, delete, change, check the basic operations, such as database creation, modification, delete, modify the operation, data insertion, deletion, modification and so on.

Execute command: HBase shell, enter HBase database

1.1 hbase help command

Execute on the command line: Help [' Command '], view the assistance command:

1.2 General Operation

1,Status: Query Server Status:

Usage: status

2,whoami: Query the current User:

Usage: WhoAmI

3,version: The current hbase to use the edition number:

Usage: Version

1.3 DDL Operations

1,create: Creating database tables, creating commands to see Help ' create '

Syntax: Create <table>, {NAME =><family>, versions => <versions>}

Example: Create ' product ', {name => ' computer ', versions => 5},{name => ' food ', versions => 3}

Description: Create a table named ' Product ' database, and create two column families, respectively: ' Computer ', ' food '

2.List: View existing tables

Usage: List

3.describe: View table structure description

Usage: Describe ' product '

4.Alter: Modify the table

Usage: Modify table structure must first disable, then modify the table, after the modification, then the Enable table.

Disable ' product '

Alter ' product ', {NAME => ' food ',versions=> 3}

Enable ' product '

5.Drop: Delete table

Usage: First disable, then drop.

Disable ' product '

Drop ' product '

1.4 DML Operations

1.put: Insert data

Grammar: Put <table>,<rowkey>,<family:column>,<value>,<timestamp>

Example: Put ' product ', ' rowkey001 ', ' computer:name ', ' ThinkPad E550 '

Insert data again: Put ' product ', ' rowkey001 ', ' Computer:price ', 4199

Description: Adds a row to the table ' product ': Rowkey is ' rowkey001 ', family name: ' Computer ', column name: ' Name ', Value: ' ThinkPad E550 ', Timestamp: system default

Insert two data, actually add two columns, return or a piece of data

2,scan: Scan table

Syntax: Scan <table>,{columns => [<family:column>,....], LIMIT => num}

HBase storage data is stored in binary form, reading is not a problem

Example: Scan ' product '

3,get: Query data

Grammar:get<table>,<rowkey>,[<family:column>,....]

Query the value of a cell under computer in the table product,rowkey001

Example: Get ' product ', ' rowkey001 '

Example: Get ' product ', ' rowkey001 ',{column=> ' computer:name '}