HDDS-11931: Populate impala.md file under Integration section

docs/04-user-guide/03-integrations/04-impala.md

@@ -1,3 +1,88 @@
+---
+sidebar_label: Impala
+---
+
 # Impala
 
-**TODO:** File a subtask under [HDDS-9858](https://issues.apache.org/jira/browse/HDDS-9858) and complete this page or section.
+Starting with version **4.2.0**, Apache Impala provides full support for querying data stored in Apache Ozone. To utilize this functionality, ensure that your Ozone version is **1.4.0** or later.
+
+## Supported Access Protocols
+
+Impala supports the following protocols for accessing Ozone data:
+
+  * `ofs`
+  * `s3a`
+
+> **Note:**
+> The `o3fs` protocol is **NOT** supported by Impala.
+
+## Supported Replication Types
+
+Impala is compatible with Ozone buckets configured with either:
+
+  * **RATIS** (Replication)
+  * **Erasure Coding**
+
+## Querying Ozone Data with Impala
+
+Impala provides two approaches to interact with Ozone:
+
+1.  Managed Tables
+2.  External Tables
+
+### Managed Tables
+
+If the Hive Warehouse Directory is located in Ozone, you can execute Impala queries without any changes, treating the Ozone file system like HDFS.
+
+**Example:**
+
+```sql
+CREATE DATABASE d1;
+
+CREATE TABLE t1 (x INT, s STRING);
+```
+
+The data will be stored under the Hive Warehouse Directory path in Ozone.
+
+#### Specifying a Custom Ozone Path
+
+You can create managed databases, tables, or partitions at a specific Ozone path using the `LOCATION` clause.
+
+**Example:**
+
+```sql
+CREATE DATABASE d1 LOCATION 'ofs://ozone1/vol1/bucket1/d1.db';
+
+CREATE TABLE t1 LOCATION 'ofs://ozone1/vol1/bucket1/table1';
+```
+
+### External Tables
+
+You can create an external table in Impala to query Ozone data.
+
+**Example:**
+
+```sql
+CREATE EXTERNAL TABLE external_table (
+  id INT,
+  name STRING
+) LOCATION 'ofs://ozone1/vol1/bucket1/table1';
+```
+
+With external tables:
+
+  * The data is expected to be created and managed by another tool.
+  * Impala queries the data as-is.
+  * The metadata is stored under the external warehouse directory.
+
+> **Note:**
+> Dropping an external table in Impala does not delete the associated data.
+
+### Using the S3A Protocol
+
+In addition to `ofs`, Impala can access Ozone via the S3 Gateway using the S3A file system. For more details, refer to:
+
+  * [The S3 Protocol](https://www.google.com/search?q=../01-client-interfaces/03-s3.md)
+  * The [Hadoop S3A documentation](https://hadoop.apache.org/docs/stable/hadoop-aws/tools/hadoop-aws/index.html)
+
+For additional information, consult the Apache Impala User Documentation on [Using Impala with Apache Ozone Storage](https://impala.apache.org/docs/build/html/topics/impala_ozone.html).