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From Boris Tyukin <bo...@boristyukin.com>
Subject Re: AVRO is the only output format with ExecuteSQL
Date Wed, 08 Aug 2018 00:29:25 GMT
Matt, you rock!! thank you!!

On Tue, Aug 7, 2018 at 5:16 PM Matt Burgess <mattyb149@gmail.com> wrote:

> Sounds good, it makes the underlying code a bit more complicated but I see
> from y’all’s points that a “separate” processor is a better user
> experience. I’m knee deep in it as we speak, hope to have a PR up in a few
> days.
>
> Thanks,
> Matt
>
>
> On Aug 7, 2018, at 5:07 PM, Andrew Grande <aperepel@gmail.com> wrote:
>
> I'd really like to see the Record suffix on the processor for
> discoverability, as already mentioned.
>
> Andrew
>
> On Tue, Aug 7, 2018, 2:16 PM Matt Burgess <mattyb149@apache.org> wrote:
>
>> Yeah that's definitely doable, most of the logic for writing a
>> ResultSet to a Flow File is localized (currently to JdbcCommon but
>> also in ResultSetRecordSet), so I wouldn't think it would be too much
>> refactor. What are folks thoughts on whether to add a Record Writer
>> property to the existing ExecuteSQL or subclass it to a new processor
>> called ExecuteSQLRecord? The former is more consistent with how the
>> SiteToSite reporting tasks work, but this is a processor. The latter
>> is more consistent with the way we've done other record processors,
>> and the benefit there is that we don't have to add a bunch of
>> documentation to fields that will be ignored (such as the Use Avro
>> Logical Types property which we wouldn't need in a ExecuteSQLRecord).
>> Having said that, we will want to offer the same options in the Avro
>> Reader/Writer, but Peter is working on that under NIFI-5405 [1].
>>
>> Thanks,
>> Matt
>>
>> [1] https://issues.apache.org/jira/browse/NIFI-5405
>>
>> On Tue, Aug 7, 2018 at 2:06 PM Andy LoPresto <alopresto@apache.org>
>> wrote:
>> >
>> > Matt,
>> >
>> > Would extending the core ExecuteSQL processor with an ExecuteSQLRecord
>> processor also work? I wonder about discoverability if only one processor
>> is present and in other places we explicitly name the processors which
>> handle records as such. If the ExecuteSQL processor handled all the SQL
>> logic, and the ExecuteSQLRecord processor just delegated most of the
>> processing in its #onTrigger() method to super, do you foresee any
>> substantial difficulties? It might require some refactoring of the parent
>> #onTrigger() to service methods.
>> >
>> >
>> > Andy LoPresto
>> > alopresto@apache.org
>> > alopresto.apache@gmail.com
>> > PGP Fingerprint: 70EC B3E5 98A6 5A3F D3C4  BACE 3C6E F65B 2F7D EF69
>> >
>> > On Aug 7, 2018, at 10:25 AM, Andrew Grande <aperepel@gmail.com> wrote:
>> >
>> > As a side note, one has to ha e a serious justification _not_ to use
>> record-based processors. The benefits, including performance, are too
>> numerous to call out here.
>> >
>> > Andrew
>> >
>> > On Tue, Aug 7, 2018, 1:15 PM Mark Payne <markap14@hotmail.com> wrote:
>> >>
>> >> Boris,
>> >>
>> >> Using a Record-based processor does not mean that you need to define a
>> schema upfront. This is
>> >> necessary if the source itself cannot provide a schema. However, since
>> it is pulling structured data
>> >> and the schema can be inferred from the database, you wouldn't need
>> to. As Matt was saying, your
>> >> Record Writer can simply be configured to Inherit Record Schema. It
>> can then write the schema to
>> >> the "avro.schema" attribute or you can choose "Do Not Write Schema".
>> This would still allow the data
>> >> to be written in JSON, CSV, etc.
>> >>
>> >> You could also have the Record Writer choose to write the schema using
>> the "avro.schema" attribute,
>> >> as mentioned above, and then have any down-stream processors read the
>> schema from this attribute.
>> >> This would allow you to use any record-oriented processors you'd like
>> without having to define the
>> >> schema yourself, if you don't want to.
>> >>
>> >> Thanks
>> >> -Mark
>> >>
>> >>
>> >>
>> >> On Aug 7, 2018, at 12:37 PM, Boris Tyukin <boris@boristyukin.com>
>> wrote:
>> >>
>> >> thanks for all the responses! it means I am not the only one
>> interested in this topic.
>> >>
>> >> Record-aware version would be really nice, but a lot of times I do not
>> want to use record-based processors since I need to define a schema for
>> input/output upfront and just want to run SQL query and get whatever
>> results back. It just adds an extra step that will be subject to
>> break/support.
>> >>
>> >> Similar to Kafka processors, it is nice to have an option of
>> record-based processor vs. message oriented processor. But if one processor
>> can do it all, it is even better :)
>> >>
>> >>
>> >> On Tue, Aug 7, 2018 at 9:28 AM Matt Burgess <mattyb149@apache.org>
>> wrote:
>> >>>
>> >>> I'm definitely interested in supporting a record-aware version as well
>> >>> (I wrote the Jira up last year [1] but haven't gotten around to
>> >>> implementing it), however I agree with Peter's comment on the Jira.
>> >>> Since ExecuteSQL is an oft-touched processor, if we had two processors
>> >>> that only differed in how the output is formatted, it could be harder
>> >>> to maintain (bugs to be fixed in two places, e.g.). I think we should
>> >>> add an optional RecordWriter property to ExecuteSQL, and the
>> >>> documentation would reflect that if it is not set, the output will be
>> >>> Avro with embedded schema as it has always been. If the RecordWriter
>> >>> is set, either the schema can be hardcoded, or they can use "Inherit
>> >>> Record Schema" even though there's no reader, and that would mimic the
>> >>> current behavior where the schema is inferred from the database
>> >>> columns and used for the writer. There is precedence for this pattern
>> >>> in the SiteToSite reporting tasks.
>> >>>
>> >>> To Bryan's point about history, Avro at the time was the most
>> >>> descriptive of the solutions because it maintains the schema and
>> >>> datatypes with the data, unlike JSON, CSV, etc. Also before the record
>> >>> readers/writers, as Bryan said, you pretty much had to split,
>> >>> transform, merge. We just need to make that processor (and others with
>> >>> specific input/output formats) "record-aware" for better performance.
>> >>>
>> >>> Regards,
>> >>> Matt
>> >>>
>> >>> [1] https://issues.apache.org/jira/browse/NIFI-4517
>> >>> On Tue, Aug 7, 2018 at 9:20 AM Bryan Bende <bbende@gmail.com>
wrote:
>> >>> >
>> >>> > I would also add that the pattern of splitting to 1 record per
flow
>> >>> > file was common before the record processors existed, and generally
>> >>> > this can/should be avoided now in favor of processing/manipulating
>> >>> > records in place, and keeping them together in large batches.
>> >>> >
>> >>> >
>> >>> >
>> >>> > On Tue, Aug 7, 2018 at 9:10 AM, Andrew Grande <aperepel@gmail.com>
>> wrote:
>> >>> > > Careful, that makes too much sense, Joe ;)
>> >>> > >
>> >>> > >
>> >>> > > On Tue, Aug 7, 2018, 8:45 AM Joe Witt <joe.witt@gmail.com>
wrote:
>> >>> > >>
>> >>> > >> i think we just need to make an ExecuteSqlRecord processor.
>> >>> > >>
>> >>> > >> thanks
>> >>> > >>
>> >>> > >> On Tue, Aug 7, 2018, 8:41 AM Mike Thomsen <
>> mikerthomsen@gmail.com> wrote:
>> >>> > >>>
>> >>> > >>> My guess is that it is due to the fact that Avro is
the only
>> record type
>> >>> > >>> that can match sql pretty closely feature to feature
on data
>> types.
>> >>> > >>> On Tue, Aug 7, 2018 at 8:33 AM Boris Tyukin <
>> boris@boristyukin.com>
>> >>> > >>> wrote:
>> >>> > >>>>
>> >>> > >>>> I've been wondering since I started learning NiFi
why
>> ExecuteSQL
>> >>> > >>>> processor only returns AVRO formatted data. All
community
>> examples I've seen
>> >>> > >>>> then convert AVRO to json and pretty much all
of them then
>> split json to
>> >>> > >>>> multiple flows.
>> >>> > >>>>
>> >>> > >>>> I found myself doing the same thing over and over
and over
>> again.
>> >>> > >>>>
>> >>> > >>>> Since everyone is doing it, is there a strong
reason why AVRO
>> is liked
>> >>> > >>>> so much? And why everyone continues doing this
3 step pattern
>> rather than
>> >>> > >>>> providing users with an option to output json
instead and
>> another option to
>> >>> > >>>> output one flowfile or multiple (one per record).
>> >>> > >>>>
>> >>> > >>>> thanks
>> >>> > >>>> Boris
>> >>
>> >>
>> >
>>
>

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