Beefy Boxes and Bandwidth Generously Provided by pair Networks
Your skill will accomplish
what the force of many cannot
 
PerlMonks  

Comment on

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

This was my first inclination as well -- note that you don't have to sort the file first if you do it this way. A potential downside is that you wind up with the entire data structure in memory.

One option to avoid the memory consumption is to use something like DBD::SQLite as mentioned above. Another option (probably slower and bulkier, but not requiring knowing DBI and SQL) might be to use Tie::MLDBM to store that hash on disk as a DB_File rather than in memory. That might wind up being larger than the original text file, but at least it'll be easy to access it again in perl.

Note: if you use Tie::MLDBM, you'll need to extract the array from the hash to a temporary array, push your data to the temporary array, and then store the temporary array back in the hash. Read the pod for more details. E.g.:

# Code not tested - consider it conceptual # use strict; use warnings; use Tie::MLDBM; tie my %hash, 'Tie::MLDBM', { 'Serialise' => 'Storable', 'Store' => 'DB_File' }, 'mybighash.dbm', O_CREAT|O_RDWR, 0640 or die $!; while (<>) { chomp; my ($id, $data) = /(\d+)\s+(.*)/; my $aref = $hash{$id} || []; push @{$aref}, $data; $hash{$id} = $aref; }

Good luck!

-xdg

Code posted by xdg on PerlMonks is public domain. It has no warranties, express or implied. Posted code may not have been tested. Use at your own risk.


In reply to Re: Re: sort large file by xdg
in thread sort large file by Murcia

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, 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, 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.
  • Log In?
    Username:
    Password:

    What's my password?
    Create A New User
    Chatterbox?
    and all is quiet...

    How do I use this? | Other CB clients
    Other Users?
    Others meditating upon the Monastery: (2)
    As of 2018-02-25 06:12 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?
      When it is dark outside I am happiest to see ...














      Results (312 votes). Check out past polls.

      Notices?