Hi,

Thanks for the informative discussion! Looking forward to using dynamic
filtering provided by Flink.

Best regards,
Jing

On Tue, Jul 19, 2022 at 3:22 AM godfrey he <godfre...@gmail.com> wrote:

> Hi, Jingong, Jark, Jing,
>
> Thanks for for the important inputs.
> Lake storage is a very important scenario, and consider more generic
> and extended case,
> I also would like to use "dynamic filtering" concept instead of
> "dynamic partition".
>
> >maybe the FLIP should also demonstrate the EXPLAIN result, which
> is also an API.
> I will add a section to describe the EXPLAIN result.
>
> >Does DPP also support streaming queries?
> Yes, but for bounded source.
>
> >it requires the SplitEnumerator must implements new introduced
> `SupportsHandleExecutionAttemptSourceEvent` interface,
> +1
>
> I will update the document and the poc code.
>
> Best,
> Godfrey
>
> Jing Zhang <beyond1...@gmail.com> 于2022年7月13日周三 20:22写道:
> >
> > Hi Godfrey,
> > Thanks for driving this discussion.
> > This is an important improvement for batch sql jobs.
> > I agree with Jingsong to expand the capability to more than just
> partitions.
> > Besides, I have two points:
> > 1. Based on FLIP-248[1],
> >
> > > Dynamic partition pruning mechanism can improve performance by avoiding
> > > reading large amounts of irrelevant data, and it works for both batch
> and
> > > streaming queries.
> >
> > Does DPP also support streaming queries?
> > It seems the proposed changes in the FLIP-248 does not work for streaming
> > queries,
> > because the dimension table might be an unbounded inputs.
> > Or does it require all dimension tables to be bounded inputs for
> streaming
> > jobs if the job wanna enable DPP?
> >
> > 2. I notice there are changes on SplitEnumerator for Hive source and File
> > source.
> > And they now depend on SourceEvent to pass PartitionData.
> > In FLIP-245, if enable speculative execution for sources based on FLIP-27
> > which use SourceEvent,
> > it requires the SplitEnumerator must implements new introduced
> > `SupportsHandleExecutionAttemptSourceEvent` interface,
> > otherwise an exception would be thrown out.
> > Since hive and File sources are commonly used for batch jobs, it's better
> > to take this point into consideration.
> >
> > Best,
> > Jing Zhang
> >
> > [1] FLIP-248:
> >
> https://cwiki.apache.org/confluence/display/FLINK/FLIP-248%3A+Introduce+dynamic+partition+pruning
> > [2] FLIP-245:
> >
> https://cwiki.apache.org/confluence/display/FLINK/FLIP-245%3A+Source+Supports+Speculative+Execution+For+Batch+Job
> >
> >
> > Jark Wu <imj...@gmail.com> 于2022年7月12日周二 13:16写道:
> >
> > > I agree with Jingsong. DPP is a particular case of Dynamic Filter
> Pushdown
> > > that the join key contains partition fields.  Extending this FLIP to
> > > general filter
> > > pushdown can benefit more optimizations, and they can share the same
> > > interface.
> > >
> > > For example, Trino Hive Connector leverages dynamic filtering to
> support:
> > > - dynamic partition pruning for partitioned tables
> > > - and dynamic bucket pruning for bucket tables
> > > - and dynamic filter pushed into the ORC and Parquet readers to perform
> > > stripe
> > >   or row-group pruning and save on disk I/O.
> > >
> > > Therefore, +1 to extend this FLIP to Dynamic Filter Pushdown (or
> Dynamic
> > > Filtering),
> > > just like Trino [1].  The interfaces should also be adapted for that.
> > >
> > > Besides, maybe the FLIP should also demonstrate the EXPLAIN result,
> which
> > > is also an API.
> > >
> > > Best,
> > > Jark
> > >
> > > [1]: https://trino.io/docs/current/admin/dynamic-filtering.html
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > On Tue, 12 Jul 2022 at 09:59, Jingsong Li <jingsongl...@gmail.com>
> wrote:
> > >
> > > > Thanks Godfrey for driving.
> > > >
> > > > I like this FLIP.
> > > >
> > > > We can restrict this capability to more than just partitions.
> > > > Here are some inputs from Lake Storage.
> > > >
> > > > The format of the splits generated by Lake Storage is roughly as
> follows:
> > > > Split {
> > > >    Path filePath;
> > > >    Statistics[] fieldStats;
> > > > }
> > > >
> > > > Stats contain the min and max of each column.
> > > >
> > > > If the storage is sorted by a column, this means that the split
> > > > filtering on that column will be very good, so not only the partition
> > > > field, but also this column is worthy of being pushed down the
> > > > RuntimeFilter.
> > > > This information can only be known by source, so I suggest that
> source
> > > > return which fields are worthy of being pushed down.
> > > >
> > > > My overall point is:
> > > > This FLIP can be extended to support Source Runtime Filter push-down
> > > > for all fields, not just dynamic partition pruning.
> > > >
> > > > What do you think?
> > > >
> > > > Best,
> > > > Jingsong
> > > >
> > > > On Fri, Jul 8, 2022 at 10:12 PM godfrey he <godfre...@gmail.com>
> wrote:
> > > > >
> > > > > Hi all,
> > > > >
> > > > > I would like to open a discussion on FLIP-248: Introduce dynamic
> > > > > partition pruning.
> > > > >
> > > > >  Currently, Flink supports static partition pruning: the
> conditions in
> > > > > the WHERE clause are analyzed
> > > > > to determine in advance which partitions can be safely skipped in
> the
> > > > > optimization phase.
> > > > > Another common scenario: the partitions information is not
> available
> > > > > in the optimization phase but in the execution phase.
> > > > > That's the problem this FLIP is trying to solve: dynamic partition
> > > > > pruning, which could reduce the partition table source IO.
> > > > >
> > > > > The query pattern looks like:
> > > > > select * from store_returns, date_dim where sr_returned_date_sk =
> > > > > d_date_sk and d_year = 2000
> > > > >
> > > > > We will introduce a mechanism for detecting dynamic partition
> pruning
> > > > > patterns in optimization phase
> > > > > and performing partition pruning at runtime by sending the
> dimension
> > > > > table results to the SplitEnumerator
> > > > > of fact table via existing coordinator mechanism.
> > > > >
> > > > > You can find more details in FLIP-248 document[1].
> > > > > Looking forward to your any feedback.
> > > > >
> > > > > [1]
> > > >
> > >
> https://cwiki.apache.org/confluence/display/FLINK/FLIP-248%3A+Introduce+dynamic+partition+pruning
> > > > > [2] POC: https://github.com/godfreyhe/flink/tree/FLIP-248
> > > > >
> > > > >
> > > > > Best,
> > > > > Godfrey
> > > >
> > >
>

Reply via email to