Pavel Stehule <pavel.stehule@gmail.com> writes:
> some customer has PostgreSQL 9.5.5. He cannot to login to database due
> broken index
> When I use single mode against to this database I got a error
> start transaction
> could not open critical system index 2679
I can't reproduce this. Removing file 2679 (pg_index_indexrelid_index)
from an otherwise-OK database leads to
$ postgres --single busted
FATAL: could not open file "base/78215/2679": No such file or directory
as expected, but
$ postgres --single -P busted
PostgreSQL stand-alone backend 9.5.15
backend>
and all seems well, in particular I can successfully do
backend> reindex index pg_index_indexrelid_index;
and then things are back to normal.
So either this is something we fixed since 9.5.5, or your summary
of the problem is missing many critical details.
regards, tom lane