Hi, On 05/06/2019 00:08, Andres Freund wrote: > Hi, > > On 2019-06-05 00:05:02 +0200, David Fetter wrote: >> Would it make sense to work toward a binary format that's not >> architecture-specific? I recall from COPY that our binary format is >> not standardized across, for example, big- and little-endian machines. > > I think you recall wrongly. It's obviously possible that we have bugs > around this, but output/input routines are supposed to handle a > endianess independent format. That usually means that you have to do > endianess conversions, but that doesn't make it non-standardized. >
Yeah, there are really 3 formats of data we have, text protocol, binary network protocol and internal on disk format. The internal on disk format will not work across big/little-endian but network binary protocol will. FWIW I don't think the code for binary format was included in original logical replication patch (I really tried to keep it as minimal as possible), but the code and protocol is pretty much ready for adding that. That said, pglogical has code which handles this (I guess Andres means that by predecessor of pgoutput) so if you look for example at the write_tuple/read_tuple/decide_datum_transfer in https://github.com/2ndQuadrant/pglogical/blob/REL2_x_STABLE/pglogical_proto_native.c that can help you give some ideas on how to approach this. -- Petr Jelinek 2ndQuadrant - PostgreSQL Solutions https://www.2ndQuadrant.com/
