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`.
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