Hive : Hive custom input/output formats .How can you use custom input/output formats in Hive?

Introduction to Custom Input/Output Formats in Hive:

Hive allows users to define custom input and output formats to read and write data in a customized format. Custom input/output formats can be used when the default input/output formats in Hive do not meet your specific data processing needs.

In this article, we will discuss the role of custom input/output formats in Hive and how to use them.

Role of Custom Input/Output Formats in Hive:

The role of custom input/output formats in Hive is to allow users to read and write data in a customized format that is not supported by the default input/output formats. Custom input/output formats can be used to read and write data from sources such as NoSQL databases, Hadoop Distributed File System (HDFS), and cloud-based storage.

Custom input/output formats are also useful when you need to process data that is not in a structured format, such as unstructured text data, JSON data, or binary data.

How to Use Custom Input/Output Formats in Hive:

To use custom input/output formats in Hive, you need to define a custom input/output format and register it with Hive. Here are the general steps to use custom input/output formats in Hive:

1. Define a custom input/output format: You can define a custom input/output format in Java by implementing the InputFormat or OutputFormat interface. You can also use existing libraries or frameworks such as Apache Avro, SequenceFile, or Parquet to define a custom input/output format.
2. Register the custom input/output format with Hive: To register the custom input/output format with Hive, you can use the ADD JAR command to add the jar file containing the custom input/output format to the classpath. You can then use the CREATE TABLE command to create a table using the custom input/output format.

Here is an example of how to create a table using a custom input/output format:

ADD JAR /path/to/custom-i-o-freshers-in-format.jar;

CREATE TABLE my_table (
  col1 string,
  col2 int
)
ROW FORMAT SERDE 'com.example.CustomSerde'
WITH SERDEPROPERTIES (
  'input.format' = 'com.example.CustomInputFormat',
  'output.format' = 'com.example.CustomOutputFormat'
)
STORED AS INPUTFORMAT 'com.example.CustomInputFormat'
OUTPUTFORMAT 'com.example.CustomOutputFormat';