Ben Kietzman created ARROW-8658: ----------------------------------- Summary: [C++][Dataset] Implement subtree pruning for FileSystemDataset::GetFragments Key: ARROW-8658 URL: https://issues.apache.org/jira/browse/ARROW-8658 Project: Apache Arrow Issue Type: Improvement Components: C++ Affects Versions: 0.17.0 Reporter: Ben Kietzman Assignee: Ben Kietzman Fix For: 1.0.0
This is a very handy optimization for large datasets with multiple partition fields. For example, given a hive-style directory {{$base_dir/a=3/}} and a filter {{"a"_ == 2}} none of its files or subdirectories need be examined. After ARROW-8318 FileSystemDataset stores only files so subtree pruning (whose implementation depended on the presence of directories to represent subtrees) was disabled. It should be possible to reintroduce this without reference to directories by examining partition expressions directly and extracting a tree structure from their subexpressions. -- This message was sent by Atlassian Jira (v8.3.4#803005)