Fix handling of BC years in to_date/to_timestamp.
Previously, a conversion such as
to_date('-44-02-01','YYYY-MM-DD')
would result in '0045-02-01 BC', as the code attempted to interpret
the negative year as BC, but failed to apply the correction needed
for our internal handling of BC years. Fix the off-by-one problem.
Also, arrange for the combination of a negative year and an
explicit "BC" marker to cancel out and produce AD. This is how
the negative-century case works, so it seems sane to do likewise.
Continue to read "year 0000" as 1 BC. Oracle would throw an error,
but we've accepted that case for a long time so I'm hesitant to
change it in a back-patch.
Per bug #16419 from Saeed Hubaishan. Back-patch to all supported
branches.
Dar Alathar-Yemen and Tom Lane
Discussion: https://postgr.es/m/16419-d8d9db0a7553f01b@postgresql.org
Branch
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REL_12_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/c5232dca8d1bbe1cab4a2d6773566ff53146340b
Modified Files
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doc/src/sgml/func.sgml | 9 +++++++
src/backend/utils/adt/formatting.c | 7 ++++--
src/test/regress/expected/horology.out | 45 ++++++++++++++++++++++++++++++++++
src/test/regress/sql/horology.sql | 12 +++++++++
4 files changed, 71 insertions(+), 2 deletions(-)