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( #3333=superdoc: print w/replies, xml ) Need Help??
Thanks erix.

I do not need to update, actually.
All I need to do is check if an identical record already exists and INSERT if not, else move onto the next 'candidate record' to insert.
I will have multiple CPUs all generating candidates for insertion into the table but the records must be unique.
I know Postgres will tell me if I try to create a duplicate record on a field I have set to UNIQUE, but I am not sure exactly how to check for that in Perl and make sure the script continues rather than dies.
Incorporating the 'dbh-per-thread/process' idea,
the pseudo-code would go something like:

foreach $CPU (@CPUs) { create dbh for this CPU; prepare_cached SELECT; prepare_cached INSERT; foreach combination { # criterion have affinity with CPU core # so criterion is always unique to CPU generate row-data; # check if row already exists; # what the SELECT sth is for if not then { insert new row; # what the INSERT sth is for } } }




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