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   the License.  You may obtain a copy of the License at

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   distributed under the License is distributed on an "AS IS" BASIS,
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`Hudi`_
========

Apache Hudi (pronounced “hoodie”) is the next generation streaming data lake platform.
Apache Hudi brings core warehouse and database functionality directly to a data lake.

.. tip::
   This article assumes that you have mastered the basic knowledge and operation of `Hudi`_.
   For the knowledge about Hudi not mentioned in this article,
   you can obtain it from its `Official Documentation`_.

By using Kyuubi, we can run SQL queries towards Hudi which is more convenient, easy to understand,
and easy to expand than directly using Spark to manipulate Hudi.

Hudi Integration
----------------

To enable the integration of Kyuubi Spark SQL engine and Hudi through
Spark DataSource V2 API, you need to:

- Referencing the Hudi :ref:`dependencies<spark-hudi-deps>`
- Setting the Spark extension and catalog :ref:`configurations<spark-hudi-conf>`

.. _spark-hudi-deps:

Dependencies
************

The **classpath** of Kyuubi Spark SQL engine with Hudi supported consists of

1. kyuubi-spark-sql-engine-\ |release|\ _2.12.jar, the engine jar deployed with a Kyuubi distribution
2. a copy of Spark distribution
3. hudi-spark<spark.version>-bundle_<scala.version>-<hudi.version>.jar (example: hudi-spark3.5-bundle_2.12:0.15.0.jar), which can be found in the `Maven Central`_

In order to make the Hudi packages visible for the runtime classpath of engines, we can use one of these methods:

1. Put the Hudi packages into ``$SPARK_HOME/jars`` directly
2. Set ``spark.jars=/path/to/hudi-spark-bundle``

.. _spark-hudi-conf:

Configurations
**************

To activate functionality of Hudi, we can set the following configurations:

.. code-block:: properties

   # Spark 3.2 to 3.5
   spark.serializer=org.apache.spark.serializer.KryoSerializer
   spark.kryo.registrator=org.apache.spark.HoodieSparkKryoRegistrar
   spark.sql.extensions=org.apache.spark.sql.hudi.HoodieSparkSessionExtension
   spark.sql.catalog.spark_catalog=org.apache.spark.sql.hudi.catalog.HoodieCatalog

Hudi Operations
---------------

Taking ``Create Table`` as a example,

.. code-block:: sql

   CREATE TABLE hudi_cow_nonpcf_tbl (
     uuid INT,
     name STRING,
     price DOUBLE
   ) USING HUDI;

Taking ``Query Data`` as a example,

.. code-block:: sql

   SELECT * FROM hudi_cow_nonpcf_tbl WHERE id < 20;

Taking ``Insert Data`` as a example,

.. code-block:: sql

   INSERT INTO hudi_cow_nonpcf_tbl SELECT 1, 'a1', 20;


Taking ``Update Data`` as a example,

.. code-block:: sql

   UPDATE hudi_cow_nonpcf_tbl SET name = 'foo', price = price * 2 WHERE id = 1;

Taking ``Delete Data`` as a example,

.. code-block:: sql

   DELETE FROM hudi_cow_nonpcf_tbl WHERE uuid = 1;

.. _Hudi: https://hudi.apache.org/
.. _Official Documentation: https://hudi.apache.org/docs/overview
.. _Maven Central: https://mvnrepository.com/artifact/org.apache.hudi