the total time is almost figured out ; i cant seem to think of a way to get process time without writing inefficient & repetitive code :(

Congratulations, you are about to start programming, start naming subroutines, subroutines that take arguments and return values, and die on critical errors (like can't open file), subroutines with meaningful names that make sense in the context of your application, subroutines whose names are part of your application vocabulary/glossary

perlintro#Writing subroutines and http://learn.perl.org/books/beginning-perl/ Chapter 8: Subroutines

i know and i have used subroutines , and i am writing subroutines for converting datetime to proper time , but cant figure out how to add up the process time

right now i am calculating total time separately and individual times by appending each process time to an hash with id as key and then consolidating ..i just cant figure out a elegant way that's it.thats why asked for help .any ideas or pseudocode would help

#!perl
use strict;    
use warnings;
use DBI;

#create db
my $dbfile = 'database.sqlite';
unlink($dbfile);
my $dbh = DBI->connect('dbi:SQLite:dbname='.$dbfile , undef , undef , 
                {RaiseError =>1, AutoCommit =>0}) or die $DBI::errstr;
$dbh->do('CREATE TABLE DATA (F1 datetime,F2 INTEGER,F3,F4)'); 
$dbh->do('CREATE TABLE STARTED (F1 datetime,F2,F3)'); 
$dbh->commit;

# load data
my $sth = $dbh->prepare('INSERT INTO DATA VALUES (?,?,?,?)');
while (<DATA>){
  chomp;
  my @f = split ',';
  if (@f==4){
    $sth->execute(@f);
  } else {
    print "Input Line $. Skipped : $_\n";
  }
}
$dbh->commit; 

# select started records
$dbh->do("INSERT INTO STARTED
          SELECT F1,F2,F3 FROM DATA WHERE F4 LIKE '%started%'");
$dbh->commit; 

# calculate duration from start
my $ar = $dbh->selectall_arrayref("
   SELECT D.F1,D.F2,D.F3,D.F4,
   (1000*strftime('%s',D.F1))+D.F2 - (1000*strftime('%s',S.F1))-S.F2
   FROM DATA AS D
   LEFT JOIN STARTED AS S
            ON D.F3 = S.F3");       
for (@$ar){
  printf "@$_\n";
} 

$dbh->disconnect;

__DATA__
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