Обсуждение: pgsql: Add error about the use of FREEZE in COPY TO

Add error about the use of FREEZE in COPY TO

Also clarify some other error wording.

Reported-by: Kyotaro Horiguchi

Discussion: https://postgr.es/m/20220802.133046.1941977979333284049.horikyota.ntt@gmail.com

Backpatch-through: master

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/acc95f29efd4f8aa60eb72a838bfd3c979fb1c5b

Modified Files
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doc/src/sgml/ref/copy.sgml          |  1 +
src/backend/commands/copy.c         | 32 +++++++++++++++++++-------------
src/test/regress/expected/copy2.out | 12 ++++++------
3 files changed, 26 insertions(+), 19 deletions(-)