pgsql: Doc: in back branches, don't call it a row constructor if it isn

Doc: in back branches, don't call it a row constructor if it isn't really.

Before commit 906bfcad7, we were not actually processing the righthand
side of a multiple-column assignment in UPDATE as a row constructor:
it was just a parenthesized list of expressions. Call it that rather
than risking confusion by people who would expect the documented behaviors
of row constructors to apply.

Back-patch to 9.5; before that, the text correctly described the construct
as a "list of independent expressions".

Discussion: <16288(dot)1479610770(at)sss(dot)pgh(dot)pa(dot)us>

Branch
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REL9_6_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/51aebcd78a4a0674737319a804ff761800fa6830

Modified Files
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doc/src/sgml/ref/update.sgml | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)