hbase shell&java 获取多版本的值

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   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 secondshbase(main):027:0> put 'testtable1','row-1','colfam1:qual1','你好,广州'0 row(s) in 0.0130 secondshbase(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 secondshbase(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 secondshbase(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 secondshbase(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 HBaseimport 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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