Doc: update the rest of section 9.4 for new function table layout.
Notably, this replaces the previous handwaving about these functions'
behavior with "character"-type inputs with some actual facts.
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/9aece5cd05f1b21b67eac0dc4f105853eec3e4eb
Modified Files
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doc/src/sgml/func.sgml | 350 ++++++++++++++++++++++++++++---------------------
1 file changed, 200 insertions(+), 150 deletions(-)