Thanks Konstantin. Just to clarify - unless the target database is resilient to duplicates, Flink's once-only configuration will not avoid duplicate updates. Mans
On Saturday, July 30, 2016 7:40 AM, Konstantin Knauf <konstantin.kn...@tngtech.com> wrote: Hi Mans, depending on the number of operations and the particular database, you might be able to use transactions. Maybe you can also find a data model, which is more resilient to these kind of failures. Cheers, Konstantin On 29.07.2016 19:26, M Singh wrote: > Hi: > > I have a use case where we need to update a counter in a db and for this > need to guarantee once only processing. If we have some entries in a > batch and it partially updates the counters and then fails, if Flink > retries the processing for that batch, some of the counters will be > updated twice (the ones which succeeded in the first batch). > > I think in order to guarantee once only processing, I will have to set > the buffer size to zero (ie, send one item at a time). > > Is there any alternative configuration or suggestion on how I can > achieve once only updates using a batch mode with partial failures ? > > Thanks > > Mans > -- Konstantin Knauf * konstantin.kn...@tngtech.com * +49-174-3413182 TNG Technology Consulting GmbH, Betastr. 13a, 85774 Unterföhring Geschäftsführer: Henrik Klagges, Christoph Stock, Dr. Robert Dahlke Sitz: Unterföhring * Amtsgericht München * HRB 135082