Re: How to recover from compressed wal archieve in windows - Mailing list pgsql-general

On Wed, May 20, 2020 at 11:36:09AM -0700, Adrian Klaver wrote:
> The next problem is that I'm pretty sure a WAL file with *.gz extension will
> not be able to be processed directly by the server. So you are going to have
> to uncompress it at some point before it gets restored.

The short answer to that question is no.  The backend does not
uncompress the segment file.  What happens is that the restore command
copies the file defined by %f to the location of %p where is gets
renamed to RECOVERYXLOG, and we expect the restore command to drop a
16MB file in og_wal/.  There is a check on the size, which would fail
if the WAL segment is still compressed.  This logic is in
RestoreArchivedFile() in xlogarchive.c.
--
Michael