Thread: pgsql: Remove unnecessary code to handle CONSTR_NOTNULL

Remove unnecessary code to handle CONSTR_NOTNULL

Commit 14e87ffa5c54 needlessly added support for CONSTR_NOTNULL entries
to StoreConstraints.  It's dead code, so remove it.

To make the situation regarding constraint creation clearer, change
comments in heap_create_with_catalog, StoreConstraints, MergeAttributes
to explain which types of constraint are used on each.

Author: 何建 (Jian He) <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CACJufxFxzqrCiUNfjJ0tQU+=nKQkQCGtGzUBude=SMOwj5VNjQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5b291d1c9c09d75982c3270bfa61d4e822087b6a

Modified Files
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src/backend/catalog/heap.c       | 13 +++----------
src/backend/commands/tablecmds.c | 15 ++++++++-------
2 files changed, 11 insertions(+), 17 deletions(-)