初识zookeeper和hbase安装与配置
一、 zookeeper
1.1 zookeeper概述
-
ZooKeeper是一个开源的分布式的，为分布式应用提供协调服务的Apache项目。
-
ZooKeeper从设计模式角度来理解：是一个基于观察者模式设计的分布式服务管理框架，它负责存储和管理大家都关心的数据，然后接受观察者的注册，一旦这些数据的状态发生变化，ZooKeeper就将负责通知已经在ZooKeeper上注册的那些观察者做出相应的反应。 例如：一组服务器集群、一组客户端，全部通过ZooKeeper注册，如果一台服务节点宕机，则ZooKeeper集群可以监测宕机几点服务器状态并通知客户端。
-
它是一个为分布式应用提供一致性服务的软件，提供的功能包括：配置维护、域名服务、分布式同步、组服务等。
二、zookeeper搭建
2.1 下载安装包
下载zookeeper的安装包，下载地址：http://zookeeper.apache.org/， 上传到linux集群环境下，规划自己的管理目录，解压安装包。
[root@master apache-zookeeper-3.6.3-bin]# cp apache-zookeeper-3.6.3-bin.tar.gz /opt/
[root@master apache-zookeeper-3.6.3-bin]# cd /opt/
[root@master apache-zookeeper-3.6.3-bin]# tar -xvf apache-zookeeper-3.6.3-bin.tar.gz
2.2 配置
进入conf目录，复制zoo-sample.cfg重命名为zoo.cfg，通过修改zoo.cfg来对zookeeper进行配置。这个名字固定写死，因为zookeeper启动会检查这个文件，根据这个配置文件里的信息来启动服务。
[root@master opt]# cd apache-zookeeper-3.6.3-bin/conf/
[root@master conf]# cp zoo_sample.cfg zoo.cfg
## 修改如下
dataDir=/opt/apache-zookeeper-3.6.3-bin/data
##在那最后添加如下
server.1=master:2888:3888
server.2=slave1:2888:3888
server.3=slave2:2888:3888
配置myid
到之前配置的zookeeper数据文件所在的目录下( /opt/apache-zookeeper-3.6.3-bin/data )生成一个文件叫myid，其中写上一个数字表明当前机器是哪一个编号的机器。
[root@master conf]# cd ..
[root@master apache-zookeeper-3.6.3-bin]# ls
bin conf docs lib LICENSE.txt NOTICE.txt README.md README_packaging.md
[root@master apache-zookeeper-3.6.3-bin]# mkdir data
[root@master apache-zookeeper-3.6.3-bin]# cd data
[root@master data]# echo 1 > myid
[root@master data]# cat myid
1
注意：文件名称必须是myid，文件内容只需要一个数字即服务器列表中当前服务器的编号。
拷贝: 将以上Zookeeper文件夹远程拷贝到另外两台服务器中(注意myid 需要修改)
[root@master opt]# scp -r apache-zookeeper-3.6.3-bin slave1:/opt
[root@master opt]# scp -r apache-zookeeper-3.6.3-bin slave2:/opt
###注意myid 需要修改
2.3 启动zookeeper
启动zookeeper的各种命令操作如下，可以使用绝对路径操作这些命令，也可使用相对路径操作这些命令，相对路径需要进到zookeeper服务的bin目录进行操作。
#启动ZK服务:
bin/zkServer.sh start
#停止ZK服务:
bin/zkServer.sh stop
#重启ZK服务:
bin/zkServer.sh restart
#查看ZK服务状态:
bin/zkServer.sh status
Zookeeper集群需要每台挨个启动。
可以用 `jps命令 `查看线程。
启动集群的时候，集群数量启动没有超过一半，状态会有错误提示，当集群启动数量超过一半就会自动转为正常状态，并且此台使集群进入正常工作状态的服务器会成为leader角色，集群中其他服务器的角色为follower。
[root@slave2 apache-zookeeper-3.6.3-bin]# ./bin/zkServer.sh start
ZooKeeper JMX enabled by default
Using config: /opt/apache-zookeeper-3.6.3-bin/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED
[root@slave1 bin]# ./zkServer.sh start
ZooKeeper JMX enabled by default
Using config: /opt/apache-zookeeper-3.6.3-bin/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED
[root@slave1 bin]# ./zkServer.sh status
ZooKeeper JMX enabled by default
Using config: /opt/apache-zookeeper-3.6.3-bin/bin/../conf/zoo.cfg
Client port found: 2181. Client address: localhost. Client SSL: false.
Mode: follower
[root@master conf]# ../bin/zkServer.sh start
ZooKeeper JMX enabled by default
Using config: /opt/apache-zookeeper-3.6.3-bin/bin/../conf/zoo.cfg
Starting zookeeper ... STARTED
[root@master conf]# ../bin/zkServer.sh status
ZooKeeper JMX enabled by default
Using config: /opt/apache-zookeeper-3.6.3-bin/bin/../conf/zoo.cfg
Client port found: 2181. Client address: localhost. Client SSL: false.
Mode: follower
[root@slave2 logs]# ./../bin/zkServer.sh status
ZooKeeper JMX enabled by default
Using config: /opt/apache-zookeeper-3.6.3-bin/bin/../conf/zoo.cfg
Client port found: 2181. Client address: localhost. Client SSL: false.
Mode: leader
2.4 启动hadoop
… 查看Hadoop搭建(一)
2.5 查看进程
[root@master conf]# jps
9157 Jps
8392 DataNode
7961 QuorumPeerMain
8508 NodeManager
9100 JournalNode
8286 NameNode
[root@slave1 bin]# jps
6176 JournalNode
6325 Jps
5719 NodeManager
5372 QuorumPeerMain
5644 DataNode
[root@slave2 logs]# jps
6512 JournalNode
5732 DataNode
5988 SecondaryNameNode
6677 Jps
5917 NodeManager
5295 QuorumPeerMain
三、HBase
3.1 介绍HBase
- Apache HBase 是 Hadoop 数据库，一个分布式、可伸缩的大数据存储。
- HBase是依赖Hadoop的。为什么HBase能存储海量的数据？因为HBase是在HDFS的基础之上构建的，HDFS是分布式文件系统。
3.2 为什么需要HBase?
- Hadoop可以很好地解决大规模数据的离线批量处理问题，但是，受限于 HadoopMapReduce编程框架的高延迟数据处理机制，使得Hadoop无法满足大规模数据实时处理应用的需求。
- HDFS面向批量访问模式，不是随机访问模式 。
- 传统的通用关系型数据库无法应对在数据规模剧增时导致的系统扩展性和性能问题（分库分表也不能很好解决）。
- 传统关系数据库在数据结构变化时一般需要停机维护；空列浪费存储空间。
- HBase在HDFS之上提供了高并发的随机写和支持实时查询，这是HDFS不具备的。
四、HBase搭建
4.1 下载上传hbase安装包
到这里下载 https://mirrors.bfsu.edu.cn/apache/hbase/ , 选择V1.4.13版本下载, 并上传到服务器;
[root@master ~]# tar -xvf hbase-1.4.13-bin.tar.gz -C /opt/
[root@master ~]# cd /opt/hbase-1.4.13/
[root@master hbase-1.4.13]# ls
bin CHANGES.txt conf docs hbase-webapps LEGAL lib LICENSE.txt NOTICE.txt README.txt
4.2 配置hbase-env.sh
[root@master conf]# cp hbase-env.sh hbase-env.sh.bak
[root@master conf]# vi hbase-env.sh
#修改
export JAVA_HOME=/usr/java/jdk1.8.0_291-amd64
// 告诉hbase使用外部的zookeeper
export HBASE_MANAGES_ZK=false
4.3 配置hbase-site.xml
[root@master conf]# cp hbase-site.xml hbase-site.xml.bak
<property>
<name>hbase.rootdir</name>
<value>hdfs://master:8020/hbase</value>
</property>
<property>
<name>hbase.cluster.distributed</name>
<value>true</value>
</property>
<property>
<name>hbase.zookeeper.quorum</name>
<value>master:2181,slave1:2181,slave2:2181</value>
</property>
### 2181为默认的 clientPort
4.4 配置regionservers
[root@master conf]# vim regionservers
master
slave1
slave2
4.5 配置分发
[root@master opt]# scp -r hbase-1.4.13/ slave1:/opt
[root@master opt]# scp -r hbase-1.4.13/ slave2:/opt
五、时间同步
5.1 安装ntp
在3台机器上安装ntp
[root@master opt]# yum install ntp
5.2 配置NTP
配置master为备选ntp时间同步服务器(当节点无法连接外网进行时间同步), slave1和slave2无法向外网同步时间时候, 向master看齐;
当master也无法同步外网时间时,都使用master的本地时钟;( 如果只有master无法同步外网, 可能时间会不同步 =.=)
[root@master opt]# vi /etc/ntp.conf
...
server 127.127.1.0 # local clock
fudge 127.127.1.0 stratum 8
...
[root@master opt]# systemctl start ntpd.service //启动ntp服务
[root@master opt]# systemctl enable ntpd.service //开机自启
[root@master opt]# ntpq -p // 查看同步时间
remote refid st t when poll reach delay offset jitter
==============================================================================
+time.cloudflare 10.12.2.186 3 u 6 64 7 173.979 -0.434 0.420
*tick.ntp.infoma .GPS. 1 u 4 64 7 180.762 12.364 9.194
+makaki.miuku.ne 218.186.3.36 2 u 8 64 7 118.586 0.959 3.578
ntp1.ams1.nl.le 130.133.1.10 2 u 5 64 7 178.315 -0.166 1.903
LOCAL(0) .LOCL. 8 l 78 64 6 0.000 0.000 0.000
//本地时钟已经成功和外面的 NTP 服务器同步。ntpq 报告中第一列 * 表示目前选择的主同步服务器，标 + 的表示有可能被用来进一步提高同步精度的次要服务器。
在slave1和slave2配置ntp
[root@slave1 opt]# vi /etc/ntp.conf
### 添加
server master
[root@slave1 opt]# systemctl restart ntpd
[root@slave1 opt]# ntpstat
synchronised to NTP server (185.209.85.222) at stratum 3
time correct to within 156 ms
polling server every 64 s
###同理配置slave2
六、启动HBase
6.1 启动
这里已经启动了hdfs, zookeeper,yarn等服务;
[root@master bin]# pwd
/opt/hbase-1.4.13/bin
[root@master bin]# ls
draining_servers.rb hbase-common.sh hirb.rb region_status.rb stop-hbase.cmd
get-active-master.rb hbase-config.cmd local-master-backup.sh replication stop-hbase.sh
graceful_stop.sh hbase-config.sh local-regionservers.sh rolling-restart.sh test
hbase hbase-daemon.sh master-backup.sh shutdown_regionserver.rb thread-pool.rb
hbase-cleanup.sh hbase-daemons.sh region_mover.rb start-hbase.cmd zookeepers.sh
hbase.cmd hbase-jruby regionservers.sh start-hbase.sh
[root@master bin]# ./start-hbase.sh
running master, logging to /opt/hbase-1.4.13/bin/../logs/hbase-root-master-master.out
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option PermSize=128m; support was removed in 8.0
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=128m; support was removed in 8.0
slave1: running regionserver, logging to /opt/hbase-1.4.13/bin/../logs/hbase-root-regionserver-slave1.out
slave2: running regionserver, logging to /opt/hbase-1.4.13/bin/../logs/hbase-root-regionserver-slave2.out
master: running regionserver, logging to /opt/hbase-1.4.13/bin/../logs/hbase-root-regionserver-master.out
slave2: Java HotSpot(TM) 64-Bit Server VM warning: ignoring option PermSize=128m; support was removed in 8.0
slave2: Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=128m; support was removed in 8.0
slave1: Java HotSpot(TM) 64-Bit Server VM warning: ignoring option PermSize=128m; support was removed in 8.0
slave1: Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=128m; support was removed in 8.0
[root@master bin]# jps
17328 Jps
8392 DataNode
7961 QuorumPeerMain
9100 JournalNode
17005 HRegionServer
8286 NameNode
16879 HMaster
[root@slave1 logs]# jps
6176 JournalNode
13315 Jps
5372 QuorumPeerMain
5644 DataNode
13167 HRegionServer
[root@slave1 logs]# jps
6176 JournalNode
13315 Jps
5372 QuorumPeerMain
5644 DataNode
13167 HRegionServer
[root@slave2 logs]# jps
6512 JournalNode
13859 Jps
5732 DataNode
5988 SecondaryNameNode
13662 HRegionServer
5295 QuorumPeerMain
6.2 进入shell界面
6.3 进入HBase Web 页面
七、使用HBase Shell 命令
1.stdent表创建
-
指定命名空间school, 表名为student , 以及列族 essential , additional 其中列族 essential 有列 name, sex, 列族 additional有列
interest
hbase(main):003:0> list_namespace NAMESPACE default hbase 2 row(s) in 0.0800 seconds -------------------------------------------- ###创建namespace hbase(main):005:0> create_namespace 'school' 0 row(s) in 1.5470 seconds hbase(main):006:0> list_namespace NAMESPACE default hbase school 3 row(s) in 0.0290 seconds -------------------------------------------- ###在命名空间school下,创建student表 hbase(main):007:0> create 'school:student',{NAME => 'essential'},{NAME => 'additional'} 0 row(s) in 3.5560 seconds => Hbase::Table - school:student -------------------------------------------- -
默认命名空间, 表名 teacher以及列族essential
hbase(main):011:0> create 'teacher',{NAME => 'essential'} 0 row(s) in 4.2930 seconds => Hbase::Table - teacher hbase(main):012:0> list TABLE school:student teacher 2 row(s) in 0.0240 seconds => ["school:student", "teacher"]
2.teacher表中删除列族essential并新增列族additional
hbase(main):013:0> alter 'teacher', {NAME => 'additional'}, {NAME => 'essential', METHOD => 'delete'}
Updating all regions with the new schema...
1/1 regions updated.
Done.
0 row(s) in 2.3850 seconds
hbase(main):016:0> desc 'teacher'
Table teacher is ENABLED
teacher
COLUMN FAMILIES DESCRIPTION
{NAME => 'additional', BLOOMFILTER => 'ROW', VERSIONS => '1', IN_MEMORY => 'false', KEEP_DELETED_CELLS => 'FALSE',
DATA_BLOCK_ENCODING => 'NONE', TTL => 'FOREVER', COMPRESSION => 'NONE', MIN_VERSIONS => '0', BLOCKCACHE => 'true',
BLOCKSIZE => '65536', REPLICATION_SCOPE => '0'}
1 row(s) in 0.0700 seconds
- 删除teacher表, 首先禁用teacher表, 再删除teacher表
hbase(main):017:0> disable 'teacher'
0 row(s) in 2.3320 seconds
hbase(main):018:0> drop'teacher'
0 row(s) in 1.2900 seconds
hbase(main):019:0> list
TABLE
school:student
1 row(s) in 0.0290 seconds
=> ["school:student"]
- 向表student里新增数据,至少5条数据,并其中某个cell至少拥有2个版本
------------------------------------------------------------------------------"""
put 'school:student', '001','essential:name','Lixibin'
put 'school:student', '001','essential:sex','男'
put 'school:student', '001','additional:interest','fzuer'
"""
hbase(main):022:0> put 'school:student', '001','essential:name','Lixibin'
0 row(s) in 0.1380 seconds
hbase(main):023:0> put 'school:student', '001','essential:sex','男'
0 row(s) in 0.0260 seconds
hbase(main):024:0> put 'school:student', '001','additional:interest','fzuer'
0 row(s) in 0.0710 seconds
------------------------------------------------------------------------------
"""
put 'school:student', '002','essential:name','Lixibin222'
put 'school:student', '002','essential:sex','女'
put 'school:student', '002','additional:interest','fzuer222'
"""
hbase(main):025:0> put 'school:student', '002','essential:name','Lixibin222'
0 row(s) in 0.0460 seconds
hbase(main):026:0> put 'school:student', '002','essential:sex','女'
0 row(s) in 0.0200 seconds
hbase(main):027:0> put 'school:student', '002','additional:interest','fzuer222'
0 row(s) in 0.0350 seconds
------------------------------------------------------------------------------
#同理再添加几组
"""
put 'school:student', '003','essential:name','Lixibin333'
put 'school:student', '002','essential:sex','女'
put 'school:student', '003','essential:sex','未知'
"""
"""
put 'school:student', '004','essential:name','Lixibin333'
put 'school:student', '004','essential:sex','略略'
"""
"""
put 'school:student', '005','essential:name','Lixibin444'
put 'school:student', '005','essential:sex','444'
put 'school:student', '005','essential:sex','555'
put 'school:student', '005','essential:sex','666'
"""
--------------------------------------------------------------------------
"""
# 设置可以设置3个版本的数据
alter 'school:student',{NAME=>'additional',VERSIONS=>3}
"""
hbase(main):060:0> alter 'school:student',{NAME=>'additional',VERSIONS=>3}
Updating all regions with the new schema...
0/1 regions updated.
1/1 regions updated.
Done.
0 row(s) in 3.2530 seconds
--------------------------------------------------------------------------
"""
put 'school:student', '006','essential:name','lixibin666'
put 'school:student', '006','essential:sex','sex666'
put 'school:student', '006','additional:interest','interest666'
put 'school:student', '006','additional:interest','interest666_6'
put 'school:student', '006','additional:interest','interest666_6_6'
"""
get 'school:student','006',{COLUMN=>'additional:interest', VERSIONS=>3}
get 'school:student','005',{COLUMN=>'essential:sex', VERSIONS=>3}
"""
hbase(main):068:0> get 'school:student','006',{COLUMN=>'additional:interest', VERSIONS=>3}
COLUMN CELL
additional:interest timestamp=1625479193891, value=interest666_6_6
additional:interest timestamp=1625479192882, value=interest666_6
additional:interest timestamp=1625479192793, value=interest666
1 row(s) in 0.0720 seconds
- 扫描表student
hbase(main):069:0> scan 'school:student'
ROW COLUMN+CELL
001 column=additional:interest, timestamp=1625478586795, value=fzuer
001 column=essential:name, timestamp=1625478584206, value=Lixibin
001 column=essential:sex, timestamp=1625478584284, value=\xE7\x94\xB7
002 column=additional:interest, timestamp=1625478636679, value=fzuer222
002 column=essential:name, timestamp=1625478635392, value=Lixibin222
002 column=essential:sex, timestamp=1625478697069, value=\xE5\xA5\xB3
003 column=essential:name, timestamp=1625478696173, value=Lixibin333
003 column=essential:sex, timestamp=1625478763282, value=\xE6\x9C\xAA\xE7\x9F\xA5
004 column=essential:name, timestamp=1625478774239, value=Lixibin333
004 column=essential:sex, timestamp=1625478775059, value=\xE7\x95\xA5\xE7\x95\xA5
005 column=essential:name, timestamp=1625478910610, value=Lixibin444
005 column=essential:sex, timestamp=1625478911901, value=666
006 column=additional:interest, timestamp=1625479193891, value=interest666_6_6
006 column=essential:name, timestamp=1625479192689, value=lixibin666
006 column=essential:sex, timestamp=1625479192758, value=sex666
6 row(s) in 0.0970 seconds
八、使用 JAVA API 操作HBase
8.1 使用IDea相关依赖
使用Maven导入相关依赖：
<dependencies>
<dependency>
<groupId>org.apache.hbasegroupId>
<artifactId>hbase-clientartifactId>
<version>1.4.13version>
dependency>
<dependency>
<groupId>junitgroupId>
<artifactId>junitartifactId>
<version>4.12version>
<scope>testscope>
dependency>
dependencies>
将hbase配置文件 hbase-site.xml 复制到resource目录下;
在C:\Windows\System32\drivers\etc 的hosts文件中添加
192.168.233.233 master
192.168.233.234 slave1
192.168.233.235 slave2
8.2 编写代码
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.util.Bytes;
import javax.sound.midi.Soundbank;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
public class MyHBaseClient {
//获取配置信息
public static Configuration conf;
static{
conf = HBaseConfiguration.create();
}
//1.判断一张表是否存在
public static boolean isExist(String tableName){
//对表操作需要使用HbaseAdmin
try {
Connection connection = ConnectionFactory.createConnection(conf);
//管理表
HBaseAdmin admin = (HBaseAdmin) connection.getAdmin();
return admin.tableExists(TableName.valueOf(tableName));
} catch (IOException e) {
e.printStackTrace();
}
return false;
}
//2.在hbase创建表
public static void createTable(String tableName,String... columnfamily){
try {
//对表操作需要使用HbaseAdmin
Connection connection = ConnectionFactory.createConnection(conf);
//管理表
HBaseAdmin admin = (HBaseAdmin) connection.getAdmin();
//1.表如果存在，请输入其他表名
if(isExist(tableName)){
System.out.println("表存在，请输入其他表名");
}else{
//2.注意:创建表的话，需要创建一个描述器
HTableDescriptor htd = new HTableDescriptor(TableName.valueOf(tableName));
//3.创建列族
for(String cf:columnfamily){
htd.addFamily(new HColumnDescriptor(cf));
}
//4.创建表
admin.createTable(htd);
System.out.println("表已经创建成功！");
}
} catch (IOException e) {
e.printStackTrace();
}
}
//3.删除hbase的表
public static void deleteTable(String tableName) {
try {
//对表操作需要使用HbaseAdmin
Connection connection = ConnectionFactory.createConnection(conf);
//管理表
HBaseAdmin admin = (HBaseAdmin) connection.getAdmin();
//1.表如果存在，请输入其他表名
if (!isExist(tableName)) {
System.out.println("表不存在");
} else {
//2.如果表存在，删除
admin.disableTable(TableName.valueOf(tableName));
admin.deleteTable(TableName.valueOf(tableName));
System.out.println("表删除了");
}
} catch (IOException e) {
e.printStackTrace();
}
}
//4.添加数据 put 'user','rowkey','info:name','tony'
public static void addRow(String tableName,String rowkey,String cf,String column,String value){
try {
//对表操作需要使用HbaseAdmin
Connection connection = ConnectionFactory.createConnection(conf);
Table t = connection.getTable(TableName.valueOf(tableName));
//1.表如果存在，请输入其他表名
if (!isExist(tableName)) {
System.out.println("表不存在");
} else {
//2.用put方式加入数据
Put p = new Put(Bytes.toBytes(rowkey));
//3.加入数据
p.addColumn(Bytes.toBytes(cf),Bytes.toBytes(column),Bytes.toBytes(value));
t.put(p);
}
} catch (IOException e) {
e.printStackTrace();
}
}
//5.删除表中一行数据
public static void deleteRow(String tableName,String rowkey,String cf ){
try {
//对表操作需要使用HbaseAdmin
Connection connection = ConnectionFactory.createConnection(conf);
Table t = connection.getTable(TableName.valueOf(tableName));
//1.表如果存在，请输入其他表名
if (!isExist(tableName)) {
System.out.println("表不存在");
} else {
//1.根据rowkey删除数据
Delete delete = new Delete(Bytes.toBytes(rowkey));
//2.删除
t.delete(delete);
System.out.println("删除成功");
}
} catch (IOException e) {
e.printStackTrace();
}
}
//6.删除多行数据
public static void deleteAll(String tableName,String... rowkeys){
try {
//对表操作需要使用HbaseAdmin
Connection connection = ConnectionFactory.createConnection(conf);
Table t = connection.getTable(TableName.valueOf(tableName));
//1.表如果存在，请输入其他表名
if (!isExist(tableName)) {
System.out.println("表不存在");
} else {
//1.把delete封装到集合
List<Delete> list = new ArrayList<Delete>();
//2.遍历
for (String row:rowkeys){
Delete d = new Delete(Bytes.toBytes(row));
list.add(d);
}
t.delete(list);
System.out.println("删除成功");
}
} catch (IOException e) {
e.printStackTrace();
}
}
//7. 扫描表数据 scan全表扫描
public static void scanAll(String tableName){
try {
//对表操作需要使用HbaseAdmin
Connection connection = ConnectionFactory.createConnection(conf);
Table t = connection.getTable(TableName.valueOf(tableName));
//1.实例scan
Scan s = new Scan();
//2.拿到Scanner对象
ResultScanner rs = t.getScanner(s);
//3.遍历
for (Result r:rs){
Cell[] cells = r.rawCells();
//遍历具体数据
for (Cell c : cells){
System.out.print("行键为："+ Bytes.toString(CellUtil.cloneRow(c))+" ");
System.out.print("列族为："+Bytes.toString(CellUtil.cloneFamily(c))+" ");
System.out.print("列名为："+Bytes.toString(CellUtil.cloneQualifier(c))+" ");
System.out.println("值为："+Bytes.toString(CellUtil.cloneValue(c)));
}
}
} catch (IOException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
// System.out.println(isExist("school:student"));
// scanAll("school:student");
createTable("school:teacher", "essential", "additional");
}
}
8.3 创建表
1. 创建表teacher并指定命名空间为school，列族为essential和additional
看到创建成功!
8.4 插入数据
插入5条数据
插入多版本数据和获取
8.5 扫描表
