rangareddy commented on issue #16344: URL: https://github.com/apache/hudi/issues/16344#issuecomment-5032542162
This issue was reviewed as part of the JIRA-migrated backlog triage. Findings: checked the Trino Hudi connector, which now lives in this repo as hudi-trino-plugin: HudiPageSourceProvider (line 314 on master) reuses the Hive connector's projectBaseColumns, which maps projected columns back to deduplicated base columns - so a parent struct should be decoded once rather than twice for multiple nested references. However, HudiMetadata does not implement applyProjection, meaning there is no dereference (nested-field) projection pushdown at all: selecting one nested field still reads and decodes the entire parent struct from Parquet. No merged change in either trinodb/trino or apache/hudi adds nested projection support to the Hudi connector, so the underlying concern from HUDI-7256 remains applicable to the in-repo plugin. Keeping this open as an incomplete capability - base-column projection works, nested-field projection pushdown is pending. Given no correctness issue has been demonstrated, the priority:blocker label may be worth revisiting. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
