Thanks for the clarification. I will try to do plain jdbc connection on
Scala/Java and will update this thread on how it goes.

*Thanks,*
*Venkat*



On Thu, Dec 7, 2023 at 9:40 AM Nicholas Chammas <nicholas.cham...@gmail.com>
wrote:

> PyMySQL has its own implementation
> <https://github.com/PyMySQL/PyMySQL/blob/f13f054abcc18b39855a760a84be0a517f0da658/pymysql/protocol.py>
>  of
> the MySQL client-server protocol. It does not use JDBC.
>
>
> On Dec 6, 2023, at 10:43 PM, Venkatesan Muniappan <
> venkatesa...@noonacademy.com> wrote:
>
> Thanks for the advice Nicholas.
>
> As mentioned in the original email, I have tried JDBC + SSH Tunnel using
> pymysql and sshtunnel and it worked fine. The problem happens only with
> Spark.
>
> *Thanks,*
> *Venkat*
>
>
>
> On Wed, Dec 6, 2023 at 10:21 PM Nicholas Chammas <
> nicholas.cham...@gmail.com> wrote:
>
>> This is not a question for the dev list. Moving dev to bcc.
>>
>> One thing I would try is to connect to this database using JDBC + SSH
>> tunnel, but without Spark. That way you can focus on getting the JDBC
>> connection to work without Spark complicating the picture for you.
>>
>>
>> On Dec 5, 2023, at 8:12 PM, Venkatesan Muniappan <
>> venkatesa...@noonacademy.com> wrote:
>>
>> Hi Team,
>>
>> I am facing an issue with SSH Tunneling in Apache Spark. The behavior is
>> same as the one in this Stackoverflow question
>> <https://stackoverflow.com/questions/68278369/how-to-use-pyspark-to-read-a-mysql-database-using-a-ssh-tunnel>
>> but there are no answers there.
>>
>> This is what I am trying:
>>
>>
>> with SSHTunnelForwarder(
>> (ssh_host, ssh_port),
>> ssh_username=ssh_user,
>> ssh_pkey=ssh_key_file,
>> remote_bind_address=(sql_hostname, sql_port),
>> local_bind_address=(local_host_ip_address, sql_port)) as tunnel:
>> tunnel.local_bind_port
>> b1_semester_df = spark.read \
>> .format("jdbc") \
>> .option("url", b2b_mysql_url.replace("<<local_bind_port>>", 
>> str(tunnel.local_bind_port)))
>> \
>> .option("query", b1_semester_sql) \
>> .option("database", 'b2b') \
>> .option("password", b2b_mysql_password) \
>> .option("driver", "com.mysql.cj.jdbc.Driver") \
>> .load()
>> b1_semester_df.count()
>>
>> Here, the b1_semester_df is loaded but when I try count on the same Df it
>> fails saying this
>>
>> 23/12/05 11:49:17 ERROR TaskSetManager: Task 0 in stage 2.0 failed 4
>> times; aborting job
>> Traceback (most recent call last):
>>   File "<stdin>", line 1, in <module>
>>   File "/usr/lib/spark/python/pyspark/sql/dataframe.py", line 382, in
>> show
>>     print(self._jdf.showString(n, 20, vertical))
>>   File
>> "/usr/lib/spark/python/lib/py4j-0.10.7-src.zip/py4j/java_gateway.py", line
>> 1257, in __call__
>>   File "/usr/lib/spark/python/pyspark/sql/utils.py", line 63, in deco
>>     return f(*a, **kw)
>>   File "/usr/lib/spark/python/lib/py4j-0.10.7-src.zip/py4j/protocol.py",
>> line 328, in get_return_value
>> py4j.protocol.Py4JJavaError: An error occurred while calling
>> o284.showString.
>> : org.apache.spark.SparkException: Job aborted due to stage failure: Task
>> 0 in stage 2.0 failed 4 times, most recent failure: Lost task 0.3 in stage
>> 2.0 (TID 11, ip-172-32-108-1.eu-central-1.compute.internal, executor 3):
>> com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link
>> failure
>>
>> However, the same is working fine with pandas df. I have tried this below
>> and it worked.
>>
>>
>> with SSHTunnelForwarder(
>> (ssh_host, ssh_port),
>> ssh_username=ssh_user,
>> ssh_pkey=ssh_key_file,
>> remote_bind_address=(sql_hostname, sql_port)) as tunnel:
>> conn = pymysql.connect(host=local_host_ip_address, user=sql_username,
>> passwd=sql_password, db=sql_main_database,
>> port=tunnel.local_bind_port)
>> df = pd.read_sql_query(b1_semester_sql, conn)
>> spark.createDataFrame(df).createOrReplaceTempView("b1_semester")
>>
>> So wanted to check what I am missing with my Spark usage. Please help.
>>
>> *Thanks,*
>> *Venkat*
>>
>>
>>
>

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