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Postgresql 8 has a pretty good Write Ahead Logging. A seperate project I
am looking at is to use the WAL as a way to syncronize two databases
that are not in a mirror mode of any type.

The scenario: Main DB has the _real_ web transactions, user list,
products, etc.  Second machine gats a clone of the main machine at a
point in time. Second machine is hauled to a trade show where the net
access is (or lack) prevents a direct line to the main db.

Second machine runs the transaction locally after a checkpoint in the
WAL is set. After the show, the WAL is replayed back into the main
machine to merge in the transactions from the satellite unit.

Other than the obvious issues of duplicated transactions (not likely
except for possibly adding a new user) and the sequence id's for the
transactions (I will have to double check that the sequencing id's are
only used as record counters), are there any "gotcha's" that others have
run across in anything similar?
-- 
James P. Kinney III          \Changing the mobile computing world/
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GPG ID: 829C6CA7 James P. Kinney III (M.S. Physics)
&lt;jkinney at localnetsolutions.com&gt;
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<li><strong><a name="00262" href="msg00262.html">[ale] database conversion</a></strong>
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