This is the same as it's implemented in ClickHouse. In fact, it has two formats: `Protobuf` (with length-delimited messages) and `ProtobufSingle` (no delimiters

This is the same as it's implemented in ClickHouse. In fact, it has two formats: `Protobuf` (with length-delimited messages) and `ProtobufSingle` (no delimiters, but only a single message can be read/written). And it is fairly common: https://clickhouse.com/docs/en/sql-reference/formats#protobuf https://clickhouse.com/docs/en/sql-reference/formats#protobu...