HBase explanation and deployment
HBase is a NoSQL database.
What is a NoSQL database?
Saving data based on Key-value
NoSQL databases do not support things
Common NoSQL databases:
HBase: HDFS based, column-oriented database
Table---> Contents
Data---> Documents
Redis: A memory-based NoSQL database that supports persistence (RDB, AOF)
Predecessor: MemCached does not support persistence
MongoDB: Document-based NoSQL database (BSON documents, JSON binary)
Cassandra: Column Oriented NoSQL Database
Table structure of HBase
article(table)
rowkey
content
author
comments
title
text
user
content
Article 1
Chicken or egg first?
……
someone
Hand spray
Chickens don't make you.
Articles...
……
……………………
architecture
HBase Environment Deployment:
Native mode---1 host: no HDFS required, data stored directly on the operating system
1. Install JAVA environment, modify environment variables
2. Install HBase
Pseudo-distribution mode---1 host: HDFS support required, data stored directly on HDFS
1. Install JAVA environment, modify environment variables
2. Deploying HDFS pseudo-distributed
3. Deploying HBase Pseudo-Distributed
Full distribution mode---3 hosts: HDFS support required, data stored directly on HDFS
1. Install JAVA environment, modify environment variables
2. Deploying HDFS Fully Distributed
3. Deploying HBase Fully Distributed
HA Full Distribution Mode---3 hosts
Environmental pre-deployment preparation:
Set environment variable vi ~/.bash_profile
HBASE_HOME=/root/training/hbase-1.3.1
export HBASE_HOME
PATH=$HBASE_HOME/bin:$PATH
export PATH
Local mode:
hbase-env.sh
28 export JAVA_HOME=/root/training/jdk1.8.0_144
hbase-site.xml
hbase.rootdir
file:///root/training/hbase-1.3.1/data
Start HBase: start-hbase.sh
pseudo-distributed mode
hbase-env.sh
129 export HBASE_MANAGES_ZK=true
hbase-site.xml
hbase.rootdir
hdfs://192.168.157.11:9000/hbase
hbase.cluster.distributed
true
hbase.zookeeper.quorum
192.168.157.11
dfs.replication
1
regionservers
192.168.157.11
Start HBase: start-hbase.sh
fully distributed model
hbase-site.xml
hbase.rootdir
hdfs://192.168.157.12:9000/hbase
hbase.cluster.distributed
true
hbase.zookeeper.quorum
192.168.157.12
dfs.replication
2
hbase.master.maxclockskew
180000
regionservers
192.168.157.13
192.168.157.14
scp -r hbase-1.3.1/ root@bigdata13:/root/training
scp -r hbase-1.3.1/ root@bigdata14:/root/training
Start HBase: start-hbase.sh
HA of HBase
No additional configuration required, only a single point on one of the slave nodes to start Hmaster
Start HBase: start-hbase.sh
bigdata13:hbase-daemon.sh start master
HBase Web Console web port: 16010
HBase command line operations:
Go to Command Line: hbase shell
View:
View table: list
Query data:
scan is equivalent to select * from table name
Get is equivalent to select * from table name where rowkey=?
Insert data:
put 'table',' row','column family': column name',' value '
put 'students', 'stu1', 'info:name', 'Tom'
Clear the table of data:
truncate 'table name'--------> The essence of truncate is to delete the table before creating it
truncate 'students'
Delete table:
disable 'table name'
drop 'table name'
