db was corrupted, ERROR: cannot freeze committed xmax; fix by deleting rows in catalog tables

Hi all,

I have a case on pg12.9 - rhel8 which crashed a long time ago and now in
log keep saying:

automatic vacuum of table "dbnamexx.pg_catalog.pg_statistic"automatic
vacuum of table "dbnamexx.pg_catalog.pg_class"automatic vacuum of table
"dbnamexx.pg_toast.pg_toast_2619"

automatic vacuum of table "dbnamexx.pg_catalog.pg_class"automatic vacuum of
table "dbnamexx.ibent.loginsession_old"automatic vacuum of table
"dbnamexx.pg_toast.pg_toast_2619"

The problem is on the user tables:

vacuum schema.tbl1_old;
ERROR: cannot freeze committed xmax ...

vacuum schema.tbl2_old;
ERROR: cannot freeze committed xmax ...

vacuum schema.tbl3_bak;
ERROR: cannot freeze committed xmax ...

vacuum schema.tbl4_old;
ERROR: cannot freeze committed xmax ...

unluckily cannot drop those tables. will return "ERROR: cannot freeze
committed xmax " too

figured out by pg_catcheck utility there are orphaned catalog entries, so
try to fix on restore database by these DML:

delete from pg_attribute where attrelid=<many id>;
delete from pg_index where indrelid=<id>;
delete from pg_statistic where starelid=<many id>;
delete from pg_constraint where conrelid=...;
delete from pg_depend where refobjid=...;
delete from pg_depend where objid=....;
delete from pg_shdepend where objid=...;

delete from pg_type where typrelid=...;
delete from pg_type where typelem=...;

delete from pg_statistic where starelid=.... and staattnum=27 and
stainherit='f';

recheck by pg_catcheck, now clean.
then vacuum now without error.

My question:
1. is it OK DML on catalog tables?
2. Are there any impacts in the future?

--
regards

ujang jaenudin | Self-Employed, DBA Consultant
http://id.linkedin.com/pub/ujang-jaenudin/12/64/bab