Hbase 基础学习教程
http://www.yiibai.com/hbase/
HBase的表结构
转自
作者：JinJ
https://www.cnblogs.com/JingJ/p/4521245.html
RowKey: 行键
ColumnFamily: 列族, HBase引入的概念：
Column
TimeStamp：在每次跟新数据时，用以标识一行数据的不同版本（事实上，TimeStamp是与列绑定的。）
如下图
HBase shell&java api操作
转自
作者：niaobirdfly
http://blog.csdn.net/hellozpc/article/details/44218057
源代码没有问题，实践如下：
- 表结构创建和查看
- 表数据查看 (scan)
- 表数据查看某行，某列 (get)
- 表删除，删除一行
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.MasterNotRunningException;
import org.apache.hadoop.hbase.ZooKeeperConnectionException;
import org.apache.hadoop.hbase.client.Delete;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.HBaseAdmin;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.util.Bytes;
public class HBaseJavaAPI {
private static Configuration conf = null;
static {
conf = HBaseConfiguration.create();
//conf.set("hbase.zookeeper.quorum", "ubuntu");
//conf.set("hbase.zookeeper.property.clientPort", "2181");
}
public static boolean isExist(String tableName) throws MasterNotRunningException, ZooKeeperConnectionException, IOException
{
HBaseAdmin hAdmin = new HBaseAdmin(conf);// 新建一个数据库管理员
return hAdmin.tableExists(tableName);
}
// 创建数据库表
public static void createTable(String tableName, String[] columnFamilys)
throws Exception {
// 新建一个数据库管理员
HBaseAdmin hAdmin = new HBaseAdmin(conf);
if (hAdmin.tableExists(tableName)) {
System.out.println("表 "+tableName+" 已存在！");
System.exit(0);
} else {
// 新建一个students表的描述
HTableDescriptor tableDesc = new HTableDescriptor(tableName);
// 在描述里添加列族
for (String columnFamily : columnFamilys) {
tableDesc.addFamily(new HColumnDescriptor(columnFamily));
}
// 根据配置好的描述建表
hAdmin.createTable(tableDesc);
System.out.println("创建表 "+tableName+" 成功!");
}
}
// 删除数据库表
public static void deleteTable(String tableName) throws Exception {
// 新建一个数据库管理员
HBaseAdmin hAdmin = new HBaseAdmin(conf);
if (hAdmin.tableExists(tableName)) {
// 关闭一个表
hAdmin.disableTable(tableName);
hAdmin.deleteTable(tableName);
System.out.println("删除表 "+tableName+" 成功！");
} else {
System.out.println("删除的表 "+tableName+" 不存在！");
System.exit(0);
}
}
// 添加一条数据
public static void addRow(String tableName, String row,
String columnFamily, String column, String value) throws Exception {
HTable table = new HTable(conf, tableName);
Put put = new Put(Bytes.toBytes(row));// 指定行
// 参数分别:列族、列、值
put.add(Bytes.toBytes(columnFamily), Bytes.toBytes(column),
Bytes.toBytes(value));
table.put(put);
}
// 删除一条(行)数据
public static void delRow(String tableName, String row) throws Exception {
HTable table = new HTable(conf, tableName);
Delete del = new Delete(Bytes.toBytes(row));
table.delete(del);
}
// 删除多条数据
public static void delMultiRows(String tableName, String[] rows)
throws Exception {
HTable table = new HTable(conf, tableName);
List<Delete> delList = new ArrayList<Delete>();
for (String row : rows) {
Delete del = new Delete(Bytes.toBytes(row));
delList.add(del);
}
table.delete(delList);
}
// 获取一条数据
public static void getRow(String tableName, String row) throws Exception {
HTable table = new HTable(conf, tableName);
Get get = new Get(Bytes.toBytes(row));
Result result = table.get(get);
// 输出结果,raw方法返回所有keyvalue数组
for (KeyValue rowKV : result.raw()) {
System.out.print("行名:" + new String(rowKV.getRow()) + " ");
System.out.print("时间戳:" + rowKV.getTimestamp() + " ");
System.out.print("列族名:" + new String(rowKV.getFamily()) + " ");
System.out.print("列名:" + new String(rowKV.getQualifier()) + " ");
System.out.println("值:" + new String(rowKV.getValue()));
}
}
// 获取所有数据
public static void getAllRows(String tableName) throws Exception {
HTable table = new HTable(conf, tableName);
Scan scan = new Scan();
ResultScanner results = table.getScanner(scan);
// 输出结果
for (Result result : results) {
for (KeyValue rowKV : result.raw()) {
System.out.print("行名:" + new String(rowKV.getRow()) + " ");
System.out.print("时间戳:" + rowKV.getTimestamp() + " ");
System.out.print("列族名:" + new String(rowKV.getFamily()) + " ");
System.out
.print("列名:" + new String(rowKV.getQualifier()) + " ");
System.out.println("值:" + new String(rowKV.getValue()));
}
}
}
public static void main(String args[]) throws Exception {
String tableName = "student";
// 第一步：创建数据库表：“student”
String[] columnFamilys = { "info", "course" };
//HBaseUtils.createTable(tableName, columnFamilys);
/*
if (HBaseJavaAPI.isTableExist(tableName)) {
// 添加第一行数据
HBaseJavaAPI.addRow(tableName, "zpc", "info", "age", "20");
HBaseJavaAPI.addRow(tableName, "zpc", "info", "sex", "boy");
HBaseJavaAPI.addRow(tableName, "zpc", "course", "china", "97");
HBaseJavaAPI.addRow(tableName, "zpc", "course", "math", "128");
HBaseJavaAPI.addRow(tableName, "zpc", "course", "english", "85");
// 添加第二行数据
HBaseJavaAPI.addRow(tableName, "henjun", "info", "age", "19");
HBaseJavaAPI.addRow(tableName, "henjun", "info", "sex", "boy");
HBaseJavaAPI.addRow(tableName, "henjun", "course", "china","90");
HBaseJavaAPI.addRow(tableName, "henjun", "course", "math","120");
HBaseJavaAPI.addRow(tableName, "henjun", "course", "english","90");
// 添加第三行数据
HBaseJavaAPI.addRow(tableName, "niaopeng", "info", "age", "18");
HBaseJavaAPI.addRow(tableName, "niaopeng", "info", "sex","girl");
HBaseJavaAPI.addRow(tableName, "niaopeng", "course", "china","100");
HBaseJavaAPI.addRow(tableName, "niaopeng", "course", "math","100");
HBaseJavaAPI.addRow(tableName, "niaopeng", "course", "english","99");
}
*/
// if (HBaseJavaAPI.isTableExist(tableName)) {
// System.out.println("**************获取所有数据***************");
// HBaseJavaAPI.getAllRows(tableName);
// }
//
// if (HBaseJavaAPI.isTableExist(tableName)) {
// System.out.println("**************获取一条(zpc)数据*************");
// HBaseJavaAPI.getRow(tableName, "zpc");
// }
// if (HBaseJavaAPI.isExist(tableName)) {
// System.out.println("************删除一条(zpc)数据************");
// HBaseJavaAPI.delRow(tableName, "zpc");
// System.out.println("**************获取一条(zpc)数据*************");
// HBaseJavaAPI.getRow(tableName, "zpc");
// }
if (HBaseJavaAPI.isExist(tableName)) {
System.out.println("***************删除数据库表**************");
HBaseJavaAPI.deleteTable(tableName);
System.out.println("表"+tableName+"存在吗？"+HBaseJavaAPI.isExist(tableName));
}else {
System.out.println(tableName + "此数据库表不存在！");
}
}
}