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https://issues.apache.org/jira/browse/ARROW-1796?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16568182#comment-16568182
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Uwe L. Korn commented on ARROW-1796:
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As an interface I would add a new kwarg to {{read_table}} called filters that
accepts a list of list of tuples. This will be in disjunctive normal form
representation. The innermost triples consist of {{(column_name, operation,
value(s))}}, e.g. {{('name', '==', 'John')}}. These innermost triples are
combined into a list and all predicates in this list and combined with {{AND}}.
The outer list is then an {{OR}} combination of the {{AND}}-combined triples.
> [Python] RowGroup filtering on file level
> -----------------------------------------
>
> Key: ARROW-1796
> URL: https://issues.apache.org/jira/browse/ARROW-1796
> Project: Apache Arrow
> Issue Type: Improvement
> Reporter: Uwe L. Korn
> Assignee: Uwe L. Korn
> Priority: Major
> Fix For: 0.11.0
>
>
> We can build upon the API defined in {{fastparquet}} for defining RowGroup
> filters:
> https://github.com/dask/fastparquet/blob/master/fastparquet/api.py#L296-L300
> and translate them into the C++ enums we will define in
> https://issues.apache.org/jira/browse/PARQUET-1158 . This should enable us to
> provide the user with a simple predicate pushdown API that we can extend in
> the background from RowGroup to Page level later on.
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