[KYUUBI apache#3060] [Subtask][apache#3059] Build the content of conn…

…ector document section

docs/integrations/index.rst → docs/connector/flink/index.rst

@@ -13,12 +13,8 @@
    See the License for the specific language governing permissions and
    limitations under the License.
 
-Integrations
-===========================
+Connectors For Flink SQL Query Engine
+=====================================
 
 .. toctree::
     :maxdepth: 2
-
-    kudu
-    delta_lake
-    delta_lake_with_azure_blob

docs/connector/hive/index.rst

@@ -0,0 +1,20 @@
+.. Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+..    http://www.apache.org/licenses/LICENSE-2.0
+
+.. Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+
+Connectors for Hive SQL Query Engine
+====================================
+
+.. toctree::
+    :maxdepth: 2

docs/connector/index.rst

@@ -0,0 +1,37 @@
+.. Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+..    http://www.apache.org/licenses/LICENSE-2.0
+
+.. Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+
+Connectors
+==========
+
+This section describes the connectors available for different kyuubi engines to access data from various data sources.
+
+.. note:: Is your connector missing?
+   `Report an feature request <https://kyuubi.apache.org/issue_tracking.html>`_ or help us document it.
+
+.. toctree::
+    :maxdepth: 2
+
+    spark/index
+
+.. toctree::
+    :maxdepth: 2
+
+    flink/index
+
+.. toctree::
+    :maxdepth: 2
+
+    hive/index

docs/connector/spark/delta_lake.rst

@@ -0,0 +1,95 @@
+.. Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+..    http://www.apache.org/licenses/LICENSE-2.0
+
+.. Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+
+`Delta Lake`_
+=============
+
+Delta lake is an open-source project that enables building a Lakehouse
+Architecture on top of existing storage systems such as S3, ADLS, GCS,
+and HDFS.
+
+.. tip::
+   This article assumes that you have mastered the basic knowledge and
+   operation of `Delta Lake`_.
+   For the knowledge about delta lake not mentioned in this article,
+   you can obtain it from its `Official Documentation`_.
+
+By using kyuubi, we can run SQL queries towards delta lake which is more
+convenient, easy to understand, and easy to expand than directly using
+spark to manipulate delta lake.
+
+Delta Lake Integration
+----------------------
+
+To enable the integration of kyuubi spark sql engine and delta lake through
+Apache Spark Datasource V2 and Catalog APIs, you need to:
+
+- Referencing the delta lake :ref:`dependencies`
+- Setting the spark extension and catalog :ref:`configurations`
+
+.. _dependencies:
+
+Dependencies
+************
+
+The **classpath** of kyuubi spark sql engine with delta lake supported consists of
+
+1. kyuubi-spark-sql-engine-|release|.jar, the engine jar deployed with kyuubi distributions
+2. a copy of spark distribution
+3. delta-core & delta-storage, which can be found in the `Maven Central`_
+
+In order to make the delta packages visible for the runtime classpath of engines, we can use one of these methods:
+
+1. Put the delta packages into ``$SPARK_HOME/jars`` directly
+2. Set ``spark.jars=/path/to/delta-core,/path/to/delta-storage``
+
+.. warning::
+   Please mind the compatibility of different Delta Lake and Spark versions, which can be confirmed on the page of `delta release notes`_.
+
+.. _configurations:
+
+Configurations
+**************
+
+To activate functionality of delta lake, we can set the following configurations:
+
+.. code-block:: properties
+
+   spark.sql.extensions=io.delta.sql.DeltaSparkSessionExtension
+   spark.sql.catalog.spark_catalog=org.apache.spark.sql.delta.catalog.DeltaCatalog
+
+Delta Lake Operations
+---------------------
+
+As for end-users, who only use a pure SQL interface, there aren't much differences between
+using a delta table and a regular hive table. Unless you are going to use some advanced
+features, but they are still SQL, just more syntax added.
+
+Taking ``CREATE A TABLE`` as a example,
+
+.. code-block:: sql
+
+   CREATE TABLE IF NOT EXISTS kyuubi_delta (
+     id INT,
+     name STRING,
+     org STRING,
+     url STRING,
+     start TIMESTAMP
+   ) USING DELTA;
+
+.. _Delta Lake: https://delta.io/
+.. _Official Documentation: https://docs.delta.io/latest/index.html
+.. _Maven Central: https://mvnrepository.com/artifact/io.delta/delta-core
+.. _Delta release notes: https://github.com/delta-io/delta/releases