I think you can do this directly in DBD::CSV with a combination of joins, user-defined functions, and the new CREATE TABLE AS SELECT ... syntax. The last two features require the SQL::Statement 1.14 or later.

Here's an example of a simple calculation with a User Defined Function 

#!/usr/bin/perl -w
use strict;
use DBI;
my $dbh=DBI->connect("dbi:CSV(RaiseError=1):csv_eol=\n");

sub MyCalc { $_[3] * 2 }
$dbh->do("CREATE FUNCTION MyCalc");

my $sth = $dbh->prepare(q{  SELECT sales,MyCalc(sales) FROM Test });
$sth->execute;
$sth->dump_results();
__END__
#
# given sales values of 2 and 5, this script outputs
#
#    2,4
#    5,10

[download]

See SQL::Statement::Functions for more on creating User Defined Functions.

To create a new table from a join of two existing tables, use something like:
CREATE TABLE new AS SELECT $cols FROM old1 JOIN old2 WHERE ...

In reply to Re: Data Set Combination by jZed
in thread Data Set Combination by Anonymous Monk

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.