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From Fabian Hueske <fhue...@gmail.com>
Subject Re: [Dev] Issue related to using Flink DataSet<T> methods
Date Wed, 01 Mar 2017 08:45:36 GMT
Hi Pawan,

in the DataSet API DataSet.print() will trigger the execution (you do not
need to call ExecutionEnvironment.execute()).
The DataSet will be printed on the standard out of the process that submits
the program. This does only work for small DataSets.
In general print() should only be used when developing jobs.

You can also use DataSet.printOnTaskManager() which writes to the standard
out of the TaskManager processes, usually to .out files in the ./log folder.

Best, Fabian

2017-03-01 7:16 GMT+01:00 Pawan Manishka Gunarathna <
pawan.manishka@gmail.com>:

> Hi,
>
> So how can I read the available records of my datasource. I saw in some
> examples that print() method will print the available data of that
> datasource. ( like files )
>
> Thanks,
> Pawan
>
>
> On Wed, Mar 1, 2017 at 11:30 AM, Xingcan Cui <xingcanc@gmail.com> wrote:
>
> > Hi Pawan,
> >
> > in Flink, most of the methods for DataSet (including print()) will just
> add
> > operators to the plan but not really run it. If the DASInputFormat has no
> > error, you can run the plan by calling environment.execute().
> >
> > Best,
> > Xingcan
> >
> > On Wed, Mar 1, 2017 at 12:17 PM, Pawan Manishka Gunarathna <
> > pawan.manishka@gmail.com> wrote:
> >
> > > Hi,
> > >
> > > I have implemented a Flink InputFormat interface related to my
> > datasource.
> > > It have our own data type as *Record*. So my class seems as follows,
> > >
> > > public class DASInputFormat implements InputFormat<Record,
> DASInputSplit>
> > {
> > > }
> > >
> > > So when I executed the print() method, my console shows the Flink
> > > execution,
> > > but nothing will print. So how can I read/print available records in
> > > my datasource
> > > table.
> > >
> > > ------------------------------------------------------------
> > > -----------------------
> > >
> > > ExecutionEnvironment environment =
> > > ExecutionEnvironment.getExecutionEnvironment();
> > > DASInputFormat dasInputFormat = new DASInputFormat(1, "SAMPLETABLE1",2,
> > > null,
> > > Long.MIN_VALUE, Long.MAX_VALUE,0, -1);
> > > DataSet<Record> dasRecords = environment.createInput(dasInputFormat);
> > > dasRecords.print();
> > >
> > > Thanks,
> > > Pawan
> > > --
> > >
> > > *Pawan Gunaratne*
> > > *Mob: +94 770373556*
> > >
> >
>
>
>
> --
>
> *Pawan Gunaratne*
> *Mob: +94 770373556*
>

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