ORC Specification

There have been two released ORC file versions:

• ORC v0 was released in Hive 0.11.
• ORC v1 was released in Hive 0.12 and ORC 1.x.

Each version of the library will detect the format version and use the appropriate reader. The library can also write the older versions of the file format to ensure that users can write files that all of their clusters can read correctly.

We are working on a new version of the file format:

• ORC v2 is a work in progress and is rapidly evolving.