I would recommend using the "SELECT ... GROUP BY" SQL statement -- it's very conscise and exactly what you want, and leverages the fact you're using DBD/CSV ..


As for your code in this post, though, you have my $row = "IP,Partition,PartitionSize,PartitionFree"; which just sets some string as the value for $row .. you need it to be all the data as an array of hashrefs .. 
my $rows = $dbh->selectall_arrayref("SELECT * FROM your_table", {Slice
+=>{}}, );
my %ips;
foreach my $row (@$rows){
  $ips{ $row->{colIP} }->{ colPartitionSize } += $row->{colPartitionSi
+ze};
  $ips{ $row->{colIP} }->{ colPartitionFree } += $row->{colPartitionFr
+ee};
}
print Dumper \%ips;

[download]
(Note that this is inefficient, as well -- would be better to use a $sth and fetch one row at a time instead of sucking in all the rows at once)

In reply to Re^3: Combine data in table by davidrw
in thread Combine data in table by DrAxeman

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