Building off of jZed's reply (and your follow-up) to your node Joining two files on common field, you can keep using DBD::CSV and just make this a SQL task: 
#!/usr/bin/perl -w
use DBI;
use strict;
my $dbh = DBI->connect("DBI:CSV:f_dir=/home/turn2sp/tmp")
        or die "Cannot connect: " . $DBI::errstr;
  $dbh->{'csv_tables'}->{'file1'} = { 'file' => 'IM.csv'};
  $dbh->{'csv_tables'}->{'file2'} = { 'file' => 'Attributes-EP2005Sep2
+3-1907.txt'};
  my $sql =<<EOS;
    UPDATE file2
    SET v_attribute_values_price_2_1 = 0                    -- is that
+ the right col??
    FROM file1 f1
    WHERE file2.v_products_model = f1.model                 -- are the
+se two lines the proper
      AND file2.v_attribute_values_price_2_1_1 = f1.size    --   FK re
+lationship ??
      AND f1.qty > 0
EOS
  $dbh->do($sql);

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In reply to Re: Parsing and modifying CSV files by davidrw
in thread Parsing and modifying CSV files by ch1

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