doc on hive csv limitations

Author: NajibAdan

presto-docs/src/main/sphinx/connector/hive.rst

@@ -1127,4 +1127,56 @@ Drop a schema::
 Hive Connector Limitations
 --------------------------
 
+SQL DELETE
+^^^^^^^^^^
+
 :doc:`/sql/delete` is only supported if the ``WHERE`` clause matches entire partitions.
+
+CSV Format Type Limitations
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+When creating tables with CSV format, all columns must be defined as ``VARCHAR`` due to 
+the underlying OpenCSVSerde limitations. `OpenCSVSerde <https://github.com/apache/hive/blob/master/serde/src/java/org/apache/hadoop/hive/serde2/OpenCSVSerde.java>`_ deserializes all CSV columns 
+as strings only. Using any other data type will result in an error similar to the following::
+
+  CREATE TABLE hive.csv.csv_fail ( 
+    id BIGINT, 
+    value INT, 
+    date_col DATE
+  ) with ( format = 'CSV' ) ;
+
+.. code-block:: none
+
+    Query failed: Hive CSV storage format only supports VARCHAR (unbounded). 
+    Unsupported columns: id integer, value integer, date_col date
+
+To work with other data types when using CSV format:
+
+1. Create the table with all the columns as ``VARCHAR``
+2. Create a view or another table that casts the columns to their desired data types
+
+Example::
+
+    -- First create table with VARCHAR columns
+    CREATE TABLE hive.csv.csv_data (
+        id VARCHAR,
+        value VARCHAR,
+        date_col VARCHAR
+    )
+    WITH (format = 'CSV');
+
+    -- Then create a view with the proper data types
+    CREATE VIEW hive.csv.csv_data_view AS
+    SELECT 
+        CAST(id AS BIGINT) AS id,
+        CAST(value AS INT) AS value,
+        CAST(date_col AS DATE) AS date_col
+    FROM hive.csv.csv_data;
+
+    -- OR another table with the proper data types
+    CREATE TABLE hive.csv.csv_data_cast AS
+    SELECT 
+        CAST(id AS BIGINT) AS id,
+        CAST(value AS INT) AS value,
+        CAST(date_col AS DATE) AS date_col
+    FROM hive.csv.csv_data;