Log Message:
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Add discussion and example about predicate locking and why "serializable"
mode isn't really serializable. I had thought this was covered already
in our docs, but I sure can't find it.
Modified Files:
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pgsql-server/doc/src/sgml:
mvcc.sgml (r2.43 -> r2.44)
(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/doc/src/sgml/mvcc.sgml.diff?r1=2.43&r2=2.44)