Ben Kietzman created ARROW-11981: ------------------------------------ Summary: [C++][Dataset][Compute] Replace UnionDataset with Union ExecNode Key: ARROW-11981 URL: https://issues.apache.org/jira/browse/ARROW-11981 Project: Apache Arrow Issue Type: Improvement Components: C++ Affects Versions: 3.0.0 Reporter: Ben Kietzman
UnionDataset allows Fragments of multiple schemas and differing file formats to be scanned together as a single Dataset. This is useful functionality but makes the Dataset interface somewhat difficult to reason about since it must be general enough to accommodate UnionDataset. After ARROW-11928 it will probably be more natural to support unioning of datasets through a subclass of ExecNode. Reconciliation of differing schemas can then be trivially handled by a full ProjectNode. Note this would obviate both ARROW-11001 and ARROW-11749. In addition, Dataset could be simplified to a concrete class containing a set of compatibly typed/formatted Fragments. -- This message was sent by Atlassian Jira (v8.3.4#803005)