Doc: document POSIX-style time zone specifications in full.
We'd glossed over most of this complexity for years, but it's hard
to avoid writing it all down now, so that we can explain what happens
when there's no "posixrules" file in the IANA time zone database.
That was at best a tiny minority situation till now, but it's likely
to become quite common in the future, so we'd better explain it.
Nonetheless, we don't really encourage people to use POSIX zone specs;
picking a named zone is almost always what you really want, unless
perhaps you're stuck with an out-of-date zone database. Therefore,
let's shove all this detail into an appendix.
Patch by me; thanks to Robert Haas for help with some awkward wording.
Discussion: https://postgr.es/m/1390.1562258309@sss.pgh.pa.us
Branch
------
REL9_5_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/089a63ec80e084a5ca380cf2462b61160d115808
Modified Files
--------------
doc/src/sgml/datatype.sgml | 40 ++-------
doc/src/sgml/datetime.sgml | 212 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 218 insertions(+), 34 deletions(-)
