habse入門級別的筆記（摘抄）

最最經常使用的指令：

1.查看hbase有什麼表 list

2.建立一個表： create '表名'， ‘字段1’， ‘字段二’，。。。

3.往表中插入一條數據：put '表名'，‘rowkey’，‘字段一：’，‘字段一欄目一名稱’，‘字段一欄目一’，.....

4.查看整個表某列的內容：scan '表名'，‘行名稱’，‘列名稱’

5.得到某行記錄：get ‘表名’，'rowkey'

6.查看錶中記錄總數：count '表名'

 

調用hbase接口應該注什麼？

1.初始化配置(如)：

  Configuration conf = new Configuration();

  conf.set("hbase.zookeeper.quorum", "10.XXX.1.XXX,10.XXX.XXX.43,10.XXX.XXX.44"); 
  conf.set("hbase.rootdir", "hdfs://10.XXX.4.XXX:9000/user/hbase");
  conf.set("hbase.cluster.distributed", "true");
  conf.set("hbase.zookeeper.property.clientPort", "XXX");
  conf.set("hbase.master.port", "XXX");
  conf.set("hbase.master.info.port", "XXX");
  conf.set("hbase.client.write.buffer", "52428800");
  conf.set("hbase.zookeeper.property.dataDir", "/data/home/zookeeper");
  conf.set("hbase.tmp.dir", "/data/home/hbase_tmp");
  conf.set("zookeeper.znode.parent", "/hbase");
  conf.set("hbase.hregion.max.filesize", "1073741824");
  conf.set("hbase.regionserver.handler.count", "20");
  conf.set("zookeeper.session.timeout", "180000");  

這個至關於hbase客戶端程序的site.xml配置文件

讀寫注意事項：

讀寫接口中傳的參數都是二進制數據流，調用的時候注意轉換

• Source Code

public static void readHbase(String table, String rowKey, String outfile, Configuration conf) throws IOException { byte[] ret = null; HTable htable = new HTable(conf, table); Get g = new Get(Bytes.toBytes(rowKey)); System.out.println(g.toString()); Result m = htable.get(g); ret = m.getValue("tarj_value".getBytes(), "Candy".getBytes()); File out_file = new File(outfile); OutputStream out = null; try { out = new FileOutputStream(out_file); out.write(ret);  out.close(); } catch (IOException e) { e.printStackTrace(); return; } } public static void writeHbase(String table, String rowKey, String infile, Configuration conf) throws IOException { File file = new File(infile); InputStream in = null; long filelength = file.length(); byte[] filecontent = null; try {  in = new FileInputStream(file); filecontent = new byte[(int)filelength]; in.read(filecontent); in.close(); } catch (IOException e) { e.printStackTrace(); 　　　　　return; }  Put put_rows = new Put(rowKey.getBytes()); put_rows.add("tarj_value".getBytes(), "Candy".getBytes(), filecontent); HTable htable = new HTable(conf, table); htable.put(put_rows); }