Thread: pgsql: Improve documentation about function volatility: mention the

Log Message:
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Improve documentation about function volatility: mention the snapshot
visibility effects in a couple of places where people are likely to look
for it.  Per discussion of recent question from Karl Nack.

Modified Files:
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    pgsql/doc/src/sgml:
        trigger.sgml (r1.55 -> r1.56)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/trigger.sgml?r1=1.55&r2=1.56)
        xfunc.sgml (r1.137 -> r1.138)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/xfunc.sgml?r1=1.137&r2=1.138)