Re: [HACKERS] Optimizer fed bad data about some system-table indexes

Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us> writes:
> If you delete the file at the end of initdb, is it recreated with the
> proper values?

OK, let's try it ...

Sure enough, if I delete the file and then start a new backend,
it's rebuilt. Not only that, it's rebuilt with the *correct* index-
size values read from pg_class! And cost_index then gets that data
passed to it.

So this code actually is able to go out and read the database, it just
doesn't want to ;-)

I'd say this whole mechanism is unnecessary; we should just build
the data on-the-fly the way it's done in write_irels(), and eliminate
all the file reading and writing code in init_irels and write_irels.
The only thing it could possibly be doing for us is saving some backend
startup time, but I'm not able to measure any difference when I delete
the init file.

I'll work on that tomorrow, unless I hear squawks of outrage from
someone who remembers what this code was for.

regards, tom lane