Repository files navigation

ORC is a self-describing type-aware columnar file format designed forHadoop workloads. It is optimized for large streaming reads, but withintegrated support for finding required rows quickly. Storing data ina columnar format lets the reader read, decompress, and process onlythe values that are required for the current query. Because ORC filesare type-aware, the writer chooses the most appropriate encoding forthe type and builds an internal index as the file is written.Predicate pushdown uses those indexes to determine which stripes in afile need to be read for a particular query and the row indexes cannarrow the search to a particular set of 10,000 rows. ORC supports thecomplete set of types in Hive, including the complex types: structs,lists, maps, and unions.

This project includes both a Java library and a C++ library for reading and writing theOptimized Row Columnar (ORC) file format. The C++ and Java libraries are completely independent of each other and will each read all versions of ORC files. But the C++ library only writes the original (Hive 0.11) version of ORC files, and will be extended in the future.

Releases:

• Latest:Apache ORC releases
• Maven Central:
• Downloads:Apache ORC downloads

The current build status:

• Master branch
• Pull Requests

Bug tracking:Apache Jira

The subdirectories are:

• c++ - the c++ reader and writer
• docker - docker scripts to build and test on various linuxes
• examples - various ORC example files that are used to test compatibility
• java - the java reader and writer
• proto - the protocol buffer definition for the ORC metadata
• site - the website and documentation
• tools - the c++ tools for reading and inspecting ORC files

• Install java 1.7 or higher
• Install maven 3 or higher
• Install cmake

To build a release version with debug information:

% mkdir build%cd build% cmake ..% make package% make test-out

To build a debug version:

% mkdir build%cd build% cmake .. -DCMAKE_BUILD_TYPE=DEBUG% make package% make test-out

To build a release version without debug information:

% mkdir build%cd build% cmake .. -DCMAKE_BUILD_TYPE=RELEASE% make package% make test-out

To build only the Java library:

%cd java% mvn package

To build only the C++ library:

% mkdir build%cd build% cmake .. -DBUILD_JAVA=OFF% make package% make test-out