> You might wish to believe that you can ignore the problem, but you can't.
> No matter what Postgres does or doesn't do, external issues such as
> network failures can create the problem of a transaction possibly being
> committed while the client remains in doubt whether it happened or not.
I think this is a well known issue and the only solution is a
transaction system covering the communication path. Since there's no
such a transaction system exists in PostgreSQL, clients should be very
carefull when try to resend DMLs as you already pointed out.
F.Y.I. pgpool-II disconnects the connection to PostgreSQL upon failure
including network problem, rather than trying to resend packet to
PostgreSQL due to the reason stated above.
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese: http://www.sraoss.co.jp
