viirya commented on issue #244: URL: https://github.com/apache/iceberg-rust/issues/244#issuecomment-2022062466
> > I think this Implement sth like ArrowProjectionVisitor is for the following two items? > > Yes, but with one extra requirement: reconstructing struct arrays. For example, when we select (`person.address.street`, `person.name`], we have projection mask `[1,2]`, and the returned schema is > > ``` > schema { > struct person { > struct address { > string street > } > string name > } > } > ``` > > But what we expect is > > ``` > schema { > string person > string name > } > ``` Yea. I think the Parquet reader cannot return the flatten schema but the pruned struct `person`. Like in query engines such as Spark, we need an additional projection to project the pruned `person` to flatten two root columns `person` and `name`. -- 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: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org