iceberg

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![Iceberg](https://iceberg.apache.org/assets/images/Iceberg-logo.svg)

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Iceberg is a high-performance format for huge analytic tables. Iceberg brings the reliability and simplicity of SQL tables to big data, while making it possible for engines like Spark, Trino, Flink, Presto, Hive and Impala to safely work with the same tables, at the same time.

Background and documentation is available at <https://iceberg.apache.org>


## Status

Iceberg is under active development at the Apache Software Foundation.

The [Iceberg format specification][iceberg-spec] is stable and new features are added with each version.

The core Java library is located in this repository and is the reference implementation for other libraries.

[Documentation][iceberg-docs] is available for all libraries and integrations.

[iceberg-docs]: https://iceberg.apache.org/docs/latest/
[iceberg-spec]: https://iceberg.apache.org/spec/

## Collaboration

Iceberg tracks issues in GitHub and prefers to receive contributions as pull requests.

Community discussions happen primarily on the [dev mailing list][dev-list] or on specific issues.

[dev-list]: mailto:dev@iceberg.apache.org


### Building

Iceberg is built using Gradle with Java 17 or 21.

* To invoke a build and run tests: `./gradlew build`
* To skip tests: `./gradlew build -x test -x integrationTest`
* To fix code style for default versions: `./gradlew spotlessApply`
* To fix code style for all versions of Spark/Hive/Flink:`./gradlew spotlessApply -DallModules`

Iceberg table support is organized in library modules:

* `iceberg-common` contains utility classes used in other modules
* `iceberg-api` contains the public Iceberg API
* `iceberg-core` contains implementations of the Iceberg API and support for Avro data files, **this is what processing engines should depend on**
* `iceberg-parquet` is an optional module for working with tables backed by Parquet files
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