I am trying to use hash array to calculate the running time of each cron job. The log file likes following: 
==
<  root 26144 c Tue Nov  2 03:10:02 2010
<  oracle 26161 c Tue Nov  2 03:10:25 2010  
<  oracle 26193 c Tue Nov  2 03:10:30 2010
<  sybase 26163 c Tue Nov  2 03:10:32 2010
>  oracle 26161 c Tue Nov  2 03:10:33 2010
<  sybase 26188 c Tue Nov  2 03:10:38 2010
>  sybase 26163 c Tue Nov  2 03:10:58 2010

==

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The leading character "<" means job started, ">" means job finished. The second field is username. Third field is jobID, which might be reused after this one is done. Since all these are daily jobs, I only care field 8 to calculate run time. Here is what I am trying to do:
==start code==
#!/usr/bin/perl
use strict;
use warnings;
use Date::Manip;

my @owner= qw/oracle sybase/;

open (FILE,"cron.log");
while(<FILE>) {
    chomp;
    next if (split /[ ]+/)[1] !~ /oracle|sybase/ ;
    my ($mode,$owner,$job_id,undef,undef,undef,undef,$timestamp,undef)
+=split /[ ]+/;
#get same jobID finish timestamp and calculate difference, 
#then save back
    ${$owner}{$job_id}=DateCalc(${$owner}{$job_id},$timestamp) if ($mo
+de=~ /^>/);
}
close(FILE);

foreach $owner(@owner){
    foreach (keys %{$owner}) { print "$owner - JobID:$_ - RunTime:${$o
+wner}{$_}\n"; };}

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==end code here==
There are three problems with my code:
1. under "strict" mode, it doesn't allow me to use number(jobID in my case) as ARRAY ref.
2. didn't consider same jobID may appeared later
3. It seems "${$owner}{$job_id}" is treated as array reference instead of hash array. When I debug above code, this variable is always null.

Seek a better approach to achieve the target. Thanks in advance!

In reply to hash array by roadtest

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