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The (key, value) pairs provided by the mapper are passed on the Loader for the TO part. The way they are written is governed by the OutputFormat. SqoopNullOutputFormat extends the OutputFormat class. The real goal of this hadoops NullOutputFormat : generates no output files  on HDFS since HDFS may not always be the destination. In our case it too HDFS is not always the destination, so , it is just named SqoopNullOutputFormat ( VB: Am I right?) we use SqoopNullOutputFormat a custom class to to delegate writing to the Loader specified in the sqoop job, it relies on the SqoopOutputFormatLoadExecutor to pass the data to the Loader via the SqoopRecordWriter. Much like how the SqoopInputFormat actually reads individual records through the SqoopRecordReader implementation, the SqoopNullOutputFormat class is a factory for SqoopRecordWriter objects; these are used to write the individual records to the final destination ( in our case the Loader)

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