Fix loss of fractional digits for large values in cash_numeric().
Money values exceeding about 18 digits (depending on lc_monetary)
could be inaccurately converted to numeric, due to select_div_scale()
deciding it didn't need to compute any fractional digits. Force
its hand by setting the dscale of one division input to equal the
number of fractional digits we need.
In passing, rearrange the logic to not do useless work in locales
where money values are considered integral.
Per bug #15925 from Slawomir Chodnicki. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/15925-da9953e2674bb5c8@postgresql.org
Branch
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REL9_6_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/30bed9f63823a13cd3fe5b1361b7f30f7123c003
Modified Files
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src/backend/utils/adt/cash.c | 58 ++++++++++++++++++++++++-------------
src/test/regress/expected/money.out | 41 +++++++++++++++++++++++++-
src/test/regress/sql/money.sql | 12 +++++++-
3 files changed, 89 insertions(+), 22 deletions(-)