Hi, During today’s column update sync, we discussed whether to keep the Avro format option for V4 manifest files. The initial inclination was to keep it because it already exists, even though Avro won’t support projection reads on manifest files (including column stats).
With both Avro and Parquet available, integrations and engines would need to choose. We expect most will pick Parquet for projection-read support. That raises a question: should we instead require Parquet for V4 manifests to reduce the cognitive and decision burden on integrations? This also aligns with Iceberg’s usual priority of read performance—especially query scan planning, where projecting column stats from manifests matters. In the sync, most people generally agreed with making V4 manifests *Parquet-only*. I’m sending this to collect any feedback or concerns from the broader community before we settle on that direction. Thanks, Steven P.S. I uploaded the recording to the YouTube channel here <https://youtu.be/dDZKzz3PKIk?t=2925> (relevant discussion started at 48:45).
