Hi everyone, While reviewing the TableMetadataBuilder PR on Iceberg-Rust <https://github.com/apache/iceberg-rust/pull/587#discussion_r1834400220> the other day, I noticed that it exposes the last-column-id to the public API, but I believe there is no need for it. This field is used to determine the next field-id when adding new fields to a schema. The last-column-id was added to the REST spec <https://github.com/apache/iceberg/pull/7445> a while ago, to make the spec in line with the reference implementation, but in hindsight, it should have been the other way around.
My suggestion is to deprecate and remove this field from the spec and code <https://github.com/apache/iceberg/pull/11514/>, as I can't think of any use case where you want to make jumps in the last-column-id (it has to be monotonically increasing). This will help clean up the APIs and the reference implementation. Would love to hear everyone's thoughts on this! Kind regards, Fokko
