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https://issues.apache.org/jira/browse/ARROW-16616?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17557566#comment-17557566
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Will Jones commented on ARROW-16616:
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{quote}In the R package we handle this by building a separate query object that
contains the Dataset (or RecordBatchReader, or Table, or whatever), and the
query object contains the filtering etc. methods.
{quote}
Yeah, I think it seems like the PR as-is would be trying to make {{Dataset}}
into this kind of query object, which I don't think is it's purpose.
{{Scanner}} seems closer to that to me, but it's also a bit of a mismatch.
{quote}That said, going that route (or the FilteredDataset path, for that
matter) feels like a path to essentially creating ibis in pyarrow.
{quote}
IMO we need to have a larger conversation about how much of Acero we want to
expose in PyArrow. We might want a low-level API for creating exec plans, and
maybe even some high-level functions like this. But seems like we should have a
design doc to think about what our vision in here and how that does relate to
developments in Ibis.
> [Python] Allow lazy evaluation of filters in Dataset and add Datset.filter
> method
> ---------------------------------------------------------------------------------
>
> Key: ARROW-16616
> URL: https://issues.apache.org/jira/browse/ARROW-16616
> Project: Apache Arrow
> Issue Type: Sub-task
> Components: Python
> Reporter: Alessandro Molina
> Assignee: Alessandro Molina
> Priority: Major
> Labels: pull-request-available
> Fix For: 9.0.0
>
> Time Spent: 0.5h
> Remaining Estimate: 0h
>
> To keep the {{Dataset}} api compatible with the {{Table}} one in terms of
> analytics capabilities, we should add a {{Dataset.filter}} method. The
> initial POC was based on {{_table_filter}} but that required materialising
> all the {{Dataset}} content after filtering as it returned an
> {{{}InMemoryDataset{}}}.
> Given that {{Scanner}} can filter a dataset without actually materialising
> the data until a final step happens, it would be good to have
> {{Dataset.filter}} return some form of lazy dataset when the filter is only
> stored aside and the Scanner is created when data is actually retrieved.
> PS: Also update {{test_dataset_filter}} test to use the {{Dataset.filter}}
> method
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