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https://issues.apache.org/jira/browse/ARROW-7224?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17298172#comment-17298172
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Ben Kietzman commented on ARROW-7224:
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Also worth noting: the case discussed in this thread (of a filter which
references each partition field exactly once and specifies an equality
condition for each) corresponds to a single subdirectory which needs to be
scanned. This is not the case for all filters, but it would be possible to add
a special case when such a prefix can be extracted. This would require the
{{Partitioning}} be explicitly constructed (so that we know without inspection
of paths what partition fields are in play), but that's fairly straightforward.
> [C++][Dataset] Partition level filters should be able to provide filtering to
> file systems
> ------------------------------------------------------------------------------------------
>
> Key: ARROW-7224
> URL: https://issues.apache.org/jira/browse/ARROW-7224
> Project: Apache Arrow
> Issue Type: Improvement
> Components: C++
> Reporter: Micah Kornfield
> Priority: Major
> Labels: dataset
>
> When providing a filter for partitions, it should be possible in some cases
> to use it to optimize file system list calls. This can greatly improve the
> speed for reading data from partitions because fewer number of
> directories/files need to be explored/expanded. I've fallen behind on the
> dataset code, but I want to make sure this issue is tracked someplace. This
> came up in SO question linked below (feel free to correct my analysis if I
> missed the functionality someplace).
> Reference:
> [https://stackoverflow.com/questions/58868584/pyarrow-parquetdataset-read-is-slow-on-a-hive-partitioned-s3-dataset-despite-u/58951477#58951477]
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