Example usage for org.apache.hadoop.mapred.lib.db DBOutputFormat setOutput

Introduction

In this page you can find the example usage for org.apache.hadoop.mapred.lib.db DBOutputFormat setOutput.

Prototype

public static void setOutput(JobConf job, String tableName, int fieldCount) 

Source Link

Document

Initializes the reduce-part of the job with the appropriate output settings

Usage

From source file:com.github.gaoyangthu.demo.mapred.DBCountPageView.java

License:Apache License

@Override
//Usage DBCountPageView [driverClass dburl]
public int run(String[] args) throws Exception {

    String driverClassName = DRIVER_CLASS;
    String url = DB_URL;// w  ww. j a va 2 s . c  o  m

    if (args.length > 1) {
        driverClassName = args[0];
        url = args[1];
    }

    initialize(driverClassName, url);

    JobConf job = new JobConf(getConf(), DBCountPageView.class);

    job.setJobName("Count Pageviews of URLs");

    job.setMapperClass(PageviewMapper.class);
    job.setCombinerClass(LongSumReducer.class);
    job.setReducerClass(PageviewReducer.class);

    DBConfiguration.configureDB(job, driverClassName, url);

    DBInputFormat.setInput(job, AccessRecord.class, "Access", null, "url", AccessFieldNames);

    DBOutputFormat.setOutput(job, "Pageview", PageviewFieldNames);

    job.setMapOutputKeyClass(Text.class);
    job.setMapOutputValueClass(LongWritable.class);

    job.setOutputKeyClass(PageviewRecord.class);
    job.setOutputValueClass(NullWritable.class);

    try {
        JobClient.runJob(job);

        boolean correct = verify();
        if (!correct) {
            throw new RuntimeException("Evaluation was not correct!");
        }
    } finally {
        shutdown();
    }
    return 0;
}

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