Well, if you don't care about memory consumption, you can always create all the groups first

my @group;

while (my $row = $sth->fetchrow_hashref) {
    push @group, []
        if !@group || $row->{foo_id} == $group[-1][0]{foo_id};
    
    push @{$group[-1]}, $row;
}

process($_) for (@group);

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In reply to Re^3: DBI & processing groups of rows by wind
in thread DBI & processing groups of rows by Anonymous Monk

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