Re: Add LZ4 compression in pg_dump

On Mon, Mar 28, 2022 at 08:36:15AM -0400, Robert Haas wrote:
> Well, I think the first thing we should do is get rid of enum
> WalCompressionMethod and use enum WalCompression instead. They've got
> the same elements and very similar names, but the WalCompressionMethod
> ones just have names like COMPRESSION_NONE, which is too generic,
> whereas WalCompressionMethod uses WAL_COMPRESSION_NONE, which is
> better. Then I think we should also rename the COMPR_ALG_* constants
> in pg_dump.h to names like DUMP_COMPRESSION_*. Once we do that we've
> got rid of all the unprefixed things that purport to be a list of
> compression algorithms.

Yes, having a centralized enum for the compression method would make
sense, along with the routines to parse and get the compression method
names. At least that would be one step towards more unity in
src/common/.

> Then, if people are willing to adopt the syntax that the
> backup_compression.c/h stuff supports as a project standard (+1 from
> me) we can go the other way and rename that stuff to be more generic,
> taking backup out of the name.

I am not sure about the specification part which is only used by base
backups that has no client-server requirements, so option values would
still require their own grammar.
--
Michael