Hive : How can you use RC file format (Record Columnar File) in Hive ?

RC File is a columnar storage format used in Hive for storing structured data. It is designed to optimize the performance of Hive queries by storing data in a way that makes it easy to access and analyze. RC files are compressed, which makes them ideal for storing large amounts of data.RCFILE stands of Record Columnar File which is another type of binary file format which offers high compression rate on the top of the rows.

RC File format works by organizing data into row groups, where each row group contains a set of rows for each column. This allows Hive to read only the columns required for a query, which reduces the amount of data that needs to be read from disk and improves query performance.

Using RC File Format in Hive:

To use RC File format in Hive, you can create a table using the following syntax:

CREATE TABLE tablename (column1 datatype1, column2 datatype2, ...)
ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.columnar.ColumnarSerDe'
STORED AS RCFILE;

In this syntax, you specify the columns and data types for your table, as well as the row format and storage format. The row format is set to “org.apache.hadoop.hive.serde2.columnar.ColumnarSerDe,” which specifies that the table will use the columnar storage format. The storage format is set to “RCFILE,” which specifies that the table will use the RC File format.

Once you have created your table using the RC File format, you can insert data into it using the standard Hive “INSERT” statement. For example:

INSERT INTO tablename (column1, column2, ...)
VALUES (value1, value2, ...);

When querying data from an RC File format table, Hive will automatically use column pruning to read only the columns required for the query. This can significantly improve query performance by reducing the amount of data that needs to be read from disk.