从HBase读取数据 [英] Read Data from HBase

问题描述

我是HBase的新手，从表格中逐行检索结果的最佳方法是什么？我想读取表格中的全部数据。我的桌子有两列家庭说col1和col2。

解决方案

我正在寻找类似的东西！
$ b Map函数

  public void map（ImmutableBytesWritable row，Result value，Context context）throws InterruptedException，IOException { b 
 $ b String x1 = new String（value.getValue（Bytes.toBytes（ColumnFamily），Bytes.toBytes（X1）））; 
 String x2 = new String（value.getValue（Bytes.toBytes（ColumnFamily），Bytes.toBytes（X2）））; 
 
 $ b} 
  

驱动程序文件： $ b

 配置config2 = new Configuration（）; 
 Job job2 = new Job（config1，kmeans2）; 
 //配置job2 
 
 job2.setJarByClass（Converge.class）; 
 job2.setMapperClass（Converge.Map.class）; 
 job2.setReducerClass（Converge.Reduce.class）; 
 job2.setInputFormatClass（TableInputFormat.class）; 
 job2.setOutputFormatClass（NullOutputFormat.class）; 
 job2.setOutputKeyClass（Text.class）; 
 job2.setOutputValueClass（Text.class）; 
 job2.getConfiguration（）。set（TableInputFormat.INPUT_TABLE，tablename）; 
  

I'm new to HBase, what's the best way to retrieve results from a table, row by row? I would like to read the entire data in the table. My table has two column families say col1 and col2.

解决方案

I was looking for something like this!

Map function

public void map(ImmutableBytesWritable row, Result value, Context context) throws InterruptedException, IOException {

            String x1 = new String(value.getValue(Bytes.toBytes("ColumnFamily"), Bytes.toBytes("X1")));
            String x2 = new String(value.getValue(Bytes.toBytes("ColumnFamily"), Bytes.toBytes("X2")));


}

Driver file:

Configuration config2 = new Configuration();
            Job job2 = new Job(config1, "kmeans2");
            //Configuration for job2

            job2.setJarByClass(Converge.class);
            job2.setMapperClass(Converge.Map.class);
            job2.setReducerClass(Converge.Reduce.class);
            job2.setInputFormatClass(TableInputFormat.class);
            job2.setOutputFormatClass(NullOutputFormat.class);
            job2.setOutputKeyClass(Text.class);
            job2.setOutputValueClass(Text.class);
            job2.getConfiguration().set(TableInputFormat.INPUT_TABLE, "tablename");                   

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