Aborting transaction on error

Hi,

Why does postgres abort the current transaction on error?
Is this actually required ANSI-SQL behaviour, or just a postgres
peculiarity.

More specifically, I have some DBI scripts which under Oracle
just insert rows into a table with a unique constraint. If they
come across a duplicate row they detect and report this error and
continue. (The duplicates are discarded as they are not needed)

However in postgres, it automatically aborts the transaction, so is
checking for the existance for a duplicate row beforehand the only way
to avoid this?

    -Mark

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Mark Rae                                       Tel: +44(0)20 7074 4648
Inpharmatica                                   Fax: +44(0)20 7074 4700
m.rae@inpharmatica.co.uk                http://www.inpharmatica.co.uk/