Your code as presented is not building a HoH or indeed any single data structure at all from the CSV data. All it is doing is reading and printing it line by line. Replace your while loop with something like this (untested):

my %HoH;
while (my $row = $csv->getline_hr($data)) {
    my $key = "$row->{latitude}.$row->{longitude}";
    # Compare
    next if exists $HoH{$key} && $row->{id} <= $HoH{$key}->{id};
    # Set (or overwrite)
    $HoH{$key} = {
        name => $row->{name},
        id   => $row->{id}
    };
}
# At this point I would return the hash (or a reference to it) but you
+ would need to change the calling line, of course

[download]

See perldsc for more on such deep/nested structures.

🦛

In reply to Re^5: Update XML Values using two primary keys by hippo
in thread Update XML Values using two primary keys by pratikpooja

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.