pgsql: doc: Fix statement about ON CONFLICT and deferrable constraints.

doc: Fix statement about ON CONFLICT and deferrable constraints.

The description of deferrable constraints in create_table.sgml states
that deferrable constraints cannot be used as conflict arbitrators in
an INSERT with an ON CONFLICT DO UPDATE clause, but in fact this
restriction applies to all ON CONFLICT clauses, not just those with DO
UPDATE. Fix this, and while at it, change the word "arbitrators" to
"arbiters", to match the terminology used elsewhere.

Author: Dean Rasheed <dean(dot)a(dot)rasheed(at)gmail(dot)com>
Discussion: https://postgr.es/m/CAEZATCWsybvZP3ce8rGcVNx-QHuDOJZDz8y=p1SzqHwjRXyV4Q@mail.gmail.com
Backpatch-through: 14

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/f188bc5145b5c2de3d00d35fba46509fa4ef0f12

Modified Files
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doc/src/sgml/ref/create_table.sgml | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)