Doc: update documentation for requirement of ORDER BY in GROUPS mode.
Commit ff4f88916 adjusted the code to enforce the SQL spec's requirement
that a window using GROUPS mode must have an ORDER BY clause. But I missed
that the documentation explicitly said you didn't have to have one.
Also minor wordsmithing in the window-function section of select.sgml.
Per Masahiko Sawada, though I didn't use his patch.
Branch
------
REL_11_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/663060e8c3832ea8388e4ae128420f76680e5fe9
Modified Files
--------------
doc/src/sgml/ref/select.sgml | 6 +++---
doc/src/sgml/syntax.sgml | 4 ++--
2 files changed, 5 insertions(+), 5 deletions(-)