http://deprecated-apache-flink-user-mailing-list-archive.369.s1.nabble.com/How-to-avoid-breaking-states-when-upgrading-Flink-job-tp7726p7859.html
Yes, Chesnay is right. You can open and close the connection in
> On Jul 7, 2016, at 11:03 AM, Chesnay Schepler <
[hidden email]> wrote:
>
> Couldn't he do the same thing in his RichFlatMap?
>
> open the db connection in open(), close it in close(), do stuff within these calls.
>
> On 07.07.2016 10:58, Kostas Kloudas wrote:
>> Hi Simon,
>>
>> If your job reads or writes to a DB, I would suggest to use one of the already existing Flink sources or sinks,
>> as this allows for efficient connection handling and managing.
>>
>> If you want to write intermediate data to a DB from an operator, then I suppose that you should implement
>> your own custom operator that opens a DB connection in the open() method and closes it at close().
>> If you are planning to do so, I think that code of your custom operator would be the same as the StreamFlatMap,
>> with the addition of the openDBConnection method in the open(), and you should also override the close() method
>> of the AbstractUdfStreamOperator to 1) call super.close() and 2) close the db connection.
>>
>> Let me know if this works,
>> Kostas
>>
>>
>>> On Jul 7, 2016, at 10:38 AM, simon peyer <
[hidden email]> wrote:
>>>
>>> Hi guys
>>>
>>> Is there a easy way to handle external DB connections inside a RichFlatMap Function?
>>>
>>> --Thanks Simon
>>
>