It seems stream_encode() uses hardcoded NullHandling::FillZero for ParquetBlockReader. Batch and streaming reader paths are unified; this call site has no config. I think maybe we could have a follow-up here if stream_encode is ever given a config or options, expose null_handling there. otherwise document that streaming encode keeps FillZero for backward compatibility.
Originally posted by @rich7420 in #1101 (comment)