pgsql: Create a separate oid range for oids assigned by genbki.pl.

Create a separate oid range for oids assigned by genbki.pl.

The changes I made in 578b229718e assigned oids below
FirstBootstrapObjectId to objects in include/catalog/*.dat files that
did not have an oid assigned, starting at the max oid explicitly
assigned. Tom criticized that for mainly two reasons:
1) It's not clear which values are manually and which explicitly
assigned.
2) The space below FirstBootstrapObjectId gets pretty crowded, and
some PostgreSQL forks have used oids >= 9000 for their own objects,
to avoid conflicting.

Thus create a new range for objects not assigned explicit oids, but
assigned by genbki.pl. For now 1-9999 is for explicitly assigned oids,
FirstGenbkiObjectId (10000) to FirstBootstrapObjectId (1200) -1 is for
genbki.pl assigned oids, and < FirstNormalObjectId (16384) is for oids
assigned during bootstrap. It's possible that we'll have to adjust
these boundaries, but there's some headroom for now.

Add a note suggesting that oids in forks should be assigned in the
9000-9999 range.

Catversion bump for obvious reasons.

Per complaint from Tom Lane.

Author: Andres Freund
Discussion: https://postgr.es/m/16845.1544393682@sss.pgh.pa.us

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/09568ec3d31bbd4854b857e8d23c197ad5b25c77

Modified Files
--------------
contrib/postgres_fdw/shippable.c | 4 ++--
src/backend/catalog/Makefile | 4 +++-
src/backend/catalog/genbki.pl | 28 ++++++++++++++++++----------
src/backend/utils/Gen_fmgrtab.pl | 12 ++++++------
src/backend/utils/fmgr/fmgr.c | 2 +-
src/include/access/transam.h | 18 +++++++++++-------
src/include/catalog/unused_oids | 8 ++++----
src/include/utils/fmgrtab.h | 2 +-
src/tools/msvc/Solution.pm | 2 +-
9 files changed, 47 insertions(+), 33 deletions(-)