MapReduce Sample Code
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MapReduce Sample Code
/* * DEMO Map/Reduce class test2 * -- Convert GPDBFormat back to TEXT */ public static class Map_test2 extends Mapper<LongWritable, GPDBWritable, Text, NullWritable> { public void map(LongWritable key, GPDBWritable value, Context context ) throws IOException { try { context.write(new Text(value.toString()), NullWritable.get()); } catch (Exception e) { throw new IOException (e.getMessage()); } } } public static void runTest2() throws Exception{ Configuration conf = new Configuration(true); Job job = new Job(conf, "test2"); job.setJarByClass(demoMR.class); job.setInputFormatClass(GPDBInputFormat.class); job.setOutputKeyLClass (Text.class); job.setOutputValueClass(NullWritable.class); job.setOutputFormatClass(TextOutputFormat.class); job.setMapperClass(Map_test2.class); GPDBInputFormat.setInputPaths (job, new Path("/demo/data/writeFromGPDB_42")); GPDBOutputFormat.setOutputPath(job, new Path("/demo/data/MRTest2")); job.waitForCompletion(true); }