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hbase shell&java 获取多版本的值

hbase shell&java 获取多版本的值

作者: wangliang938 | 来源:发表于2017-04-01 15:01 被阅读20次

转自:http://blog.csdn.net/wind520/article/details/39344805
在HBase中 一个row对应的相同的列只会有一行。使用scan 或get 得到都是最新的数据,如果我们对这某一row所对应的列进行了更改操作后,并不会多生成一条数据,不会像数据库一样,插入时多生成一条记录,在HBase中对同一条数据的修改或插入都只是put操作,最终看到的都是最新的数据,其它的数据在不同的version中保存,默认是隐藏的,通过时间戳区分,Hbase默认保存最近的三个版本,如何才能看到这些旧版本的数据了?
插入测试数据:

hbase(main):026:0> put 'testtable1','row-1','colfam1:qual1','你好,中国'  
0 row(s) in 0.0200 seconds  
  
hbase(main):027:0> put 'testtable1','row-1','colfam1:qual1','你好,广州'  
0 row(s) in 0.0130 seconds  
  
hbase(main):027:0> put 'testtable1','row-1','colfam1:qual1','welcome,hbase'  
0 row(s) in 0.0130 seconds  

下面3个命令,只显示最近的三个版本

hbase(main):015:0> get 'testtable1','row-1',{COLUMN=>'colfam1:qual1',VERSIONS=>10}  
COLUMN                             CELL                                                                                               
 colfam1:qual1                     timestamp=1410943676361, value=welcome\xEF\xBC\x8Chbase                                            
 colfam1:qual1                     timestamp=1410942935244, value=\xE4\xBD\xA0\xE5\xA5\xBD\xEF\xBC\x8C\xE5\xB9\xBF\xE5\xB7\x9E        
 colfam1:qual1                     timestamp=1410942917285, value=\xE4\xBD\xA0\xE5\xA5\xBD\xEF\xBC\x8C\xE4\xB8\xAD\xE5\x9B\xBD        
3 row(s) in 0.0270 seconds  
  
hbase(main):016:0> scan 'testtable1', {COLUMN=>'colfam1:qual1',VERSIONS=>10}  
ROW                                COLUMN+CELL                                                                                        
 row-1                             column=colfam1:qual1, timestamp=1410943676361, value=welcome\xEF\xBC\x8Chbase                      
 row-1                             column=colfam1:qual1, timestamp=1410942935244, value=\xE4\xBD\xA0\xE5\xA5\xBD\xEF\xBC\x8C\xE5\xB9  
                                   \xBF\xE5\xB7\x9E                                                                                   
 row-1                             column=colfam1:qual1, timestamp=1410942917285, value=\xE4\xBD\xA0\xE5\xA5\xBD\xEF\xBC\x8C\xE4\xB8  
                                   \xAD\xE5\x9B\xBD                                                                                   
1 row(s) in 0.0300 seconds  
  
hbase(main):017:0> scan 'testtable1', {FILTER => "PrefixFilter ('row-1')",COLUMN=>'colfam1:qual1',VERSIONS=>10}  
ROW                                COLUMN+CELL                                                                                        
 row-1                             column=colfam1:qual1, timestamp=1410943676361, value=welcome\xEF\xBC\x8Chbase                      
 row-1                             column=colfam1:qual1, timestamp=1410942935244, value=\xE4\xBD\xA0\xE5\xA5\xBD\xEF\xBC\x8C\xE5\xB9  
                                   \xBF\xE5\xB7\x9E                                                                                   
 row-1                             column=colfam1:qual1, timestamp=1410942917285, value=\xE4\xBD\xA0\xE5\xA5\xBD\xEF\xBC\x8C\xE4\xB8  
                                   \xAD\xE5\x9B\xBD                                                                                   
1 row(s) in 0.0220 seconds  

下面2个命令,可以显示所有的版本

hbase(main):018:0> scan 'testtable1',{FILTER => "(QualifierFilter (>=, 'binary:qual1')))",RAW => true, VERSIONS => 10}  
ROW                                COLUMN+CELL                                                                                        
 row-1                             column=colfam1:qual1, timestamp=1410943676361, value=welcome\xEF\xBC\x8Chbase                      
 row-1                             column=colfam1:qual1, timestamp=1410942935244, value=\xE4\xBD\xA0\xE5\xA5\xBD\xEF\xBC\x8C\xE5\xB9  
                                   \xBF\xE5\xB7\x9E                                                                                   
 row-1                             column=colfam1:qual1, timestamp=1410942917285, value=\xE4\xBD\xA0\xE5\xA5\xBD\xEF\xBC\x8C\xE4\xB8  
                                   \xAD\xE5\x9B\xBD                                                                                   
 row-1                             column=colfam1:qual1, timestamp=1410936055137, value=\xE4\xB8\xAD\xE5\x9B\xBD\xE7\xAC\xAC\xE4\xB8  
                                   \x89\xE6\x96\xB9\xE7\x9A\x84\xE4\xBA\x8C\xE6\x96\xB9\xE7\x9A\x84                                   
 row-1                             column=colfam1:qual1, timestamp=1410936031157, value=\xE4\xB8\xAD\xE5\x9B\xBD\xE7\xAC\xAC\xE4\xB8  
                                   \x89\xE6\x96\xB9\xE7\x9A\x84                                                                       
1 row(s) in 0.0290 seconds  
  
hbase(main):019:0> scan 'testtable1',{FILTER => "PrefixFilter ('row-1')",RAW => true, VERSIONS => 10}  
ROW                                COLUMN+CELL                                                                                        
 row-1                             column=colfam1:qual1, timestamp=1410943676361, value=welcome\xEF\xBC\x8Chbase                      
 row-1                             column=colfam1:qual1, timestamp=1410942935244, value=\xE4\xBD\xA0\xE5\xA5\xBD\xEF\xBC\x8C\xE5\xB9  
                                   \xBF\xE5\xB7\x9E                                                                                   
 row-1                             column=colfam1:qual1, timestamp=1410942917285, value=\xE4\xBD\xA0\xE5\xA5\xBD\xEF\xBC\x8C\xE4\xB8  
                                   \xAD\xE5\x9B\xBD                                                                                   
 row-1                             column=colfam1:qual1, timestamp=1410936055137, value=\xE4\xB8\xAD\xE5\x9B\xBD\xE7\xAC\xAC\xE4\xB8  
                                   \x89\xE6\x96\xB9\xE7\x9A\x84\xE4\xBA\x8C\xE6\x96\xB9\xE7\x9A\x84                                   
 row-1                             column=colfam1:qual1, timestamp=1410936031157, value=\xE4\xB8\xAD\xE5\x9B\xBD\xE7\xAC\xAC\xE4\xB8  
                                   \x89\xE6\x96\xB9\xE7\x9A\x84                                                                       
 row-1                             column=colfam2:col-0, timestamp=1410935938913, value=val-1.0                                       
 row-1                             column=colfam2:col-1, timestamp=1410935938921, value=val-1.1                                       
 row-1                             column=colfam2:col-2, timestamp=1410935938927, value=val-1.2                                       
 row-1                             column=colfam2:col-3, timestamp=1410935938929, value=val-1.3                                       
 row-1                             column=colfam2:col-4, timestamp=1410935938932, value=val-1.4                                       
 row-1                             column=colfam2:col-5, timestamp=1410935938935, value=val-1.5                                       
 row-1                             column=colfam2:col-6, timestamp=1410935938937, value=val-1.6                                       
 row-1                             column=colfam2:col-7, timestamp=1410935938939, value=val-1.7                                       
 row-1                             column=colfam2:col-8, timestamp=1410935938941, value=val-1.8                                       
 row-1                             column=colfam2:col-9, timestamp=1410935938944, value=val-1.9                                       
                                     
1 row(s) in 0.0690 seconds  

用java代码测试:

package client;  
// cc GetExample Example application retrieving data from HBase  
import org.apache.hadoop.conf.Configuration;  
import org.apache.hadoop.hbase.HBaseConfiguration;  
import org.apache.hadoop.hbase.client.Get;  
import org.apache.hadoop.hbase.client.HTable;  
import org.apache.hadoop.hbase.client.Result;  
import org.apache.hadoop.hbase.util.Bytes;  
  
import util.HBaseHelper;  
  
import java.io.IOException;  
  
import org.apache.hadoop.hbase.KeyValue;  
  
import java.util.List;  
public class GetExample {  
  
  public static void main(String[] args) throws IOException {  
    // vv GetExample  
    Configuration conf = HBaseConfiguration.create(); // co GetExample-1-CreateConf Create the configuration.  
    conf.set("hbase.zookeeper.property.clientPort", "2181");    
    conf.set("hbase.zookeeper.quorum", "jifeng01");    
    conf.set("zookeeper.znode.parent", "/hbase");  
    /*/ ^^ GetExample 
    HBaseHelper helper = HBaseHelper.getHelper(conf); 
    if (!helper.existsTable("testtable1")) { 
      helper.createTable("testtable1", "colfam1"); 
    } 
    */  
    //vv GetExample  
    HTable table = new HTable(conf, "testtable1"); // co GetExample-2-NewTable Instantiate a new table reference.  
  
    Get get = new Get(Bytes.toBytes("row-1")); // co GetExample-3-NewGet Create get with specific row.  
    get.setMaxVersions();  
    get.addColumn(Bytes.toBytes("colfam1"), Bytes.toBytes("qual1"));  
    Result result = table.get(get);  
    List<KeyValue> list = result.list();   
     for(final KeyValue kv:list){  
        // System.out.println("value: "+ kv+ " str: "+Bytes.toString(kv.getValue()));  
         System.out.println(String.format("row:%s, family:%s, qualifier:%s, qualifiervalue:%s, timestamp:%s.",   
                 Bytes.toString(kv.getRow()),   
                 Bytes.toString(kv.getFamily()),   
                 Bytes.toString(kv.getQualifier()),   
                 Bytes.toString(kv.getValue()),  
                 kv.getTimestamp()));       
     }  
    /* 
    get.addColumn(Bytes.toBytes("colfam1"), Bytes.toBytes("qual1")); // co GetExample-4-AddCol Add a column to the get. 
     
    Result result = table.get(get); // co GetExample-5-DoGet Retrieve row with selected columns from HBase. 
 
    byte[] val = result.getValue(Bytes.toBytes("colfam1"), 
      Bytes.toBytes("qual1")); // co GetExample-6-GetValue Get a specific value for the given column. 
 
    System.out.println("Value: " + Bytes.toString(val)); // co GetExample-7-Print Print out the value while converting it back. 
     
    */  
    // ^^ GetExample  
  }  
}  

输出结果:

row:row-1, family:colfam1, qualifier:qual1, qualifiervalue:welcome,hbase, timestamp:1410943676361.  
row:row-1, family:colfam1, qualifier:qual1, qualifiervalue:你好,广州, timestamp:1410942935244.  
row:row-1, family:colfam1, qualifier:qual1, qualifiervalue:你好,中国, timestamp:1410942917285.  

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