UNDO and partially commited transactions

I was reading the WAL documentation, and found out that UNDO is going to let 
PostgreSQL allow to make partial rollbacks on invalid transactions.

What does this exactly mean? Does it mean that if I have 6 Inserts in between 
a begin work - commit work some will get through and the ones with errors no?

Saludos... :-)

-- 
Cualquiera administra un NT.
Ese es el problema, que cualquiera administre.
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Martin Marques                  |        mmarques@unl.edu.ar
Programador, Administrador      |       Centro de Telematica                      Universidad Nacional
        del Litoral
 
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