Doc: document EXTRACT(JULIAN ...), improve Julian Date explanation.
For some reason, the "julian" option for extract()/date_part() has
never gotten listed in the manual. Also, while Appendix B mentioned
in passing that we don't conform to the usual astronomical definition
that a Julian date starts at noon UTC, it was kind of vague about what
we do instead. Clarify that, and add an example showing how to get
the astronomical definition if you want it.
It's been like this for ages, so back-patch to all supported branches.
Discussion: https://postgr.es/m/1197050.1619123213@sss.pgh.pa.us
Branch
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REL_10_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/64d617de3c595226804e850b8c8a45517f794932
Modified Files
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doc/src/sgml/datetime.sgml | 46 ++++++++++++++++++++++++++++++++++++++++------
doc/src/sgml/func.sgml | 22 +++++++++++++++++++++-
2 files changed, 61 insertions(+), 7 deletions(-)