What is the SequenceFileInputFormat in Hadoop?

In Hadoop, SequenceFileInputFormat is used to read files in sequence. It is a specific compressed binary file format which passes data between the output of one MapReduce job to the input of some other MapReduce job.

In Hadoop, SequenceFileInputFormat is a class that is used to read data stored in Hadoop’s SequenceFile format. The SequenceFile is a binary file format used for storing key-value pairs, which is often used as an intermediate data format in Hadoop MapReduce jobs.

When you use SequenceFileInputFormat as the input format for your Hadoop MapReduce job, it means that your job will process data stored in SequenceFiles. The key and value types specified for the SequenceFileInputFormat determine how the data is read and presented to your MapReduce job.

Here’s a brief explanation:

• Key-Value Pairs: The SequenceFile format stores data as a sequence of binary key-value pairs.
• SequenceFileInputFormat: This input format is used to read data from SequenceFiles in Hadoop MapReduce jobs.
• Usage: When you set SequenceFileInputFormat as the input format for your Hadoop job, it allows the MapReduce framework to understand how to read the data from the SequenceFile.

Here’s an example of how you might use it in a Hadoop MapReduce job configuration:

This way, the job is configured to read input data in the SequenceFile format.