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# Hudi
Apache Hudi (Incubating) (pronounced Hoodie) stands for `Hadoop Upserts Deletes and Incrementals`. 
Hudi manages the storage of large analytical datasets on DFS (Cloud stores, HDFS or any Hadoop FileSystem compatible storage).

### Features
* Upsert support with fast, pluggable indexing
* Atomically publish data with rollback support
* Snapshot isolation between writer & queries 
* Savepoints for data recovery
* Manages file sizes, layout using statistics
* Async compaction of row & columnar data
* Timeline metadata to track lineage
 
Hudi provides the ability to query via three types of views:
 * **Read Optimized View** - Provides excellent snapshot query performance via purely columnar storage (e.g. [Parquet](https://parquet.apache.org/))
 * **Incremental View** - Provides a change stream with records inserted or updated after a point in time.
 * **Real-time View** - Provides snapshot queries on real-time data, using a combination of columnar & row-based storage (e.g Parquet + [Avro](http://avro.apache.org/docs/current/mr.html))

Learn more about Hudi at [https://hudi.apache.org](https://hudi.apache.org)

### Building Apache Hudi from source {#building-hudi}

Hudi requires Java 8 to be installed on a *nix system. Check out [code](https://github.com/apache/incubator-hudi) and 
normally build the maven project, from command line:

```
# Checkout code and build
git clone https://github.com/apache/incubator-hudi.git && cd incubator-hudi
mvn clean package -DskipTests -DskipITs
```

### Quickstart

Try [https://hudi.apache.org/quickstart.html](https://hudi.apache.org/quickstart.html) to quickly explore Hudi's capabilities using spark-shell.