https://pgeoghegan.blogspot.com/2018/03/decoding-pgfilenodemapdata.html
Peter Geoghegan's blog: Decoding pg_filenode.map files with pg_filenodemapdata
From time to time, you may need to figure out which file in a PostgreSQL data directory corresponds to a particular table or index in the da...
peter geoghegans blogmap filesdecoding
https://commitfest.postgresql.org/patch/3041/
Logical replication failure "ERROR: could not map filenode "base/13237/442428" to relation OID"...