pgsql: Doc: remove obsolete, confused about rowtype I/O syntax.

Doc: remove obsolete, confused <note> about rowtype I/O syntax.

This <note> was originally written to describe the double levels
of de-backslashing encountered when a backslash-aware string
literal is used to hold the text representation of a composite
value.  It still made sense when we switched to mostly using E'...'
syntax for that type of literal.  However, commit f77de4b0c mangled
it completely by changing the example literal to be SQL-standard.
The extra pass of de-backslashing described in the text doesn't
actually occur with the example as written, unless you happen to
be using standard_conforming_strings = off.

We could restore this <note> to self-consistency by reverting the
change from f77de4b0c, but on the whole I judge that its time has
passed.  standard_conforming_strings = off is nearly obsolete,
and may soon be fully so.  But without that, the behavior isn't
so complicated as to justify a discursive note.  I observe that
the nearby section about array I/O syntax has no equivalent text,
although that syntax is equally subject to this issue.

Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/2998401.1767038920@sss.pgh.pa.us
Discussion: https://postgr.es/m/3279216.1767072538@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d6542f8dfc6c7db9b491a4f0b1ea082cfa4537eb

Modified Files
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doc/src/sgml/rowtypes.sgml | 24 ------------------------
1 file changed, 24 deletions(-)