Major Description
The deflate codec is described as:
The "deflate" codec writes the length of the compressed data (as an Avro-encoded long), followed by data compressed using the deflate algorithm as specified in RFC 1951, and typically implemented using the zlib library. Note that this format (unlike the "zlib format" in RFC 1950) does not have a checksum.
The codec no longer has the length of the data encoded, as this is handled by the file format.