pgsql: Don't set a fast default for anything but a plain table

Don't set a fast default for anything but a plain table

The fast default code added in Release 11 omitted to check that the
table a fast default was being added to was a plain table. Thus one
could be added to a foreign table, which predicably blows up. Here we
perform that check.

In addition, on the back branches, since some of these might have
escaped into the wild, if we encounter a missing value for
an attribute of something other than a plain table we ignore it.

Fixes bug #17056

Backpatch to release 11,

Reviewed by: Andres Freund, Álvaro Herrera and Tom Lane

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/0a4efdc7ebf2584257b166c87e82797eb92815b5

Modified Files
--------------
src/backend/catalog/heap.c                 | 10 +++++++++-
src/test/regress/expected/fast_default.out | 19 +++++++++++++++++++
src/test/regress/sql/fast_default.sql      | 14 ++++++++++++++
3 files changed, 42 insertions(+), 1 deletion(-)