Incremental scan was not available with jdbc operator till now. +1 for
adding that.

-Priyanka

On Mon, May 9, 2016 at 8:56 AM, Mohit Jotwani <[email protected]> wrote:

> +1 for incremental data.
>
> Regards,
> Mohit
> On 9 May 2016 19:59, "Yogi Devendra" <[email protected]> wrote:
>
> > +1 for incremental data fetching.
> > for fetchDirection variable; it is better to get inputs from original
> > author (if possible).
> >
> > ~ Yogi
> >
> > On 9 May 2016 at 19:04, Akshay Gore <[email protected]> wrote:
> >
> > > +1 for incremental data fetching. This is a must-have feature.
> > >
> > > -Akshay
> > > On 09-May-2016 3:39 pm, "Sandeep Deshmukh" <[email protected]>
> > > wrote:
> > >
> > > > Hi All,
> > > >
> > > > I am using JdbcPOJOInputOperator to ingest data from mysql to HDFS. I
> > > > observed that  once the existing data is ingested, newly added data
> in
> > > > mysql is not ingested. At the same time, if I add some data to mysql
> > when
> > > > the ingestion is still going on, the newly added data is also
> ingested
> > on
> > > > HDFS.
> > > >
> > > > In the code, fetching data in batches in achieved using fetchSize
> > > parameter
> > > > that limits the number of tuples to fetch per result set and
> pageNumber
> > > is
> > > > used internally to manage the offset calculation as ( fetchSize *
> > > > pageNumber). The pageNumber is incremented per window.
> > > >
> > > > When the existing tuples are ingested, there is no further data
> ingest
> > > but
> > > > the pageNumber variable is still incremented. This results is trying
> to
> > > > fetch data that is beyond the number of tuples in the
> > table/queryresult.
> > > >
> > > > Changing offset calculations to tuples read so far will fix this
> issue
> > > and
> > > > the operator can then be used to poll for newer data in the table.
> > > >
> > > > If you need to have a quick look at the code:
> > https://github.com/apache/
> > > > incubator-apex-malhar/blob/master/library/src/main/java/
> > > > com/datatorrent/lib/db/jdbc/JdbcPOJOInputOperator.java
> > > >
> > > > Side observation: fetchDirection variable is unused in the code. Will
> > > > remove it from the class.
> > > >
> > > > Would like get your thoughts on my observations. I will create a JIRA
> > and
> > > > open a PR based on inputs received on this thread.
> > > >
> > > > Regards,
> > > > Sandeep
> > > >
> > >
> >
>

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