edu.yale.cs.hadoopdb.benchmark.AggTaskSmallDB.java Source code

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Here is the source code for edu.yale.cs.hadoopdb.benchmark.AggTaskSmallDB.java

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/**
 * Copyright 2009 HadoopDB Team (http://db.cs.yale.edu/hadoopdb/hadoopdb.html)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package edu.yale.cs.hadoopdb.benchmark;

import java.io.IOException;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Iterator;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.DoubleWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.TextOutputFormat;
import org.apache.hadoop.util.ToolRunner;

import edu.yale.cs.hadoopdb.connector.DBConst;
import edu.yale.cs.hadoopdb.connector.DBWritable;
import edu.yale.cs.hadoopdb.exec.DBJobBase;
import edu.yale.cs.hadoopdb.util.HDFSUtil;

/**
 * HadoopDB's implementation of Small Aggregation Task
 * http://database.cs.brown.edu/projects/mapreduce-vs-dbms/
 */
public class AggTaskSmallDB extends DBJobBase {

    public static void main(String[] args) throws Exception {
        int res = ToolRunner.run(new Configuration(), new AggTaskSmallDB(), args);
        System.exit(res);
    }

    @Override
    protected JobConf configureJob(String... args) throws Exception {

        JobConf conf = new JobConf(this.getClass());
        conf.setJobName("aggregation_db_small");

        conf.setOutputKeyClass(Text.class);
        conf.setOutputValueClass(DoubleWritable.class);
        conf.setOutputFormat(TextOutputFormat.class);

        conf.setMapperClass(Map.class);
        conf.setReducerClass(Reduce.class);

        if (args.length < 1) {
            throw new RuntimeException("Incorrect arguments provided for " + this.getClass());
        }

        // OUTPUT properties
        Path outputPath = new Path(args[0]);
        HDFSUtil.deletePath(outputPath);
        FileOutputFormat.setOutputPath(conf, outputPath);

        conf.set(DBConst.DB_RELATION_ID, "UserVisits");
        conf.set(DBConst.DB_RECORD_READER, AggUserVisitsRecord.class.getName());
        conf.set(DBConst.DB_SQL_QUERY,
                "SELECT SUBSTRING(sourceIP, 1, 7) AS subSourceIP, SUM(adRevenue) AS sumAdRevenue FROM UserVisits GROUP BY subSourceIP;");

        return conf;
    }

    @Override
    protected int printUsage() {
        System.out.println("<output_dir>");
        return -1;
    }

    static class Map extends MapReduceBase
            implements Mapper<LongWritable, AggUserVisitsRecord, Text, DoubleWritable> {

        protected Text outputKey = new Text();
        protected DoubleWritable outputValue = new DoubleWritable();

        public void map(LongWritable key, AggUserVisitsRecord value, OutputCollector<Text, DoubleWritable> output,
                Reporter reporter) throws IOException {

            outputKey.set(value.getSubSourceIP());
            outputValue.set(value.getSumAdRevenue());
            output.collect(outputKey, outputValue);

        }
    }

    public static class Reduce extends MapReduceBase
            implements Reducer<Text, DoubleWritable, Text, DoubleWritable> {

        protected DoubleWritable outputValue = new DoubleWritable();

        public void reduce(Text key, Iterator<DoubleWritable> values, OutputCollector<Text, DoubleWritable> output,
                Reporter reporter) throws IOException {

            double sum = 0;
            while (values.hasNext()) {
                sum += values.next().get();
            }

            outputValue.set(sum);
            output.collect(key, outputValue);
        }
    }

    static class AggUserVisitsRecord implements DBWritable {
        private String subSourceIP;
        private double sumAdRevenue;

        public String getSubSourceIP() {
            return subSourceIP;
        }

        public double getSumAdRevenue() {
            return sumAdRevenue;
        }

        @Override
        public void readFields(ResultSet resultSet) throws SQLException {
            this.subSourceIP = resultSet.getString("subSourceIP");
            this.sumAdRevenue = resultSet.getDouble("sumAdRevenue");
        }

        @Override
        public void write(PreparedStatement statement) throws SQLException {
            throw new UnsupportedOperationException("No write() impl.");
        }
    }

}