If, by 'null' and 'blank', you mean undef, note that length undef is zero. That's also true of the empty string, ''. This may work for you,

if (length $day[5]) {
    print $day[5];
}
else {
    print '00:00:00';
}
[download]

After Compline,
Zaxo

Thank you for your help! I guess that I was not using the undef correctly? Now, when the filed in the array is blank "00:00:00" is put into the array. My code now works and looks like this:

#!/usr/bin/perl -w

use DBI;
my $dbh = DBI->connect('DBI:ODBC:PERL', {AutoCommit => 1},)
    or die "Couldn't connect to database: " . DBI->errstr;

$log = print "Enter FS log name> ";
chomp($log);

open($LogDate, ">>LogDate.txt");

while ($log = <>) {
    open(DATA,$log);
        @file = <DATA>;
    close(DATA);

    foreach $line (@file) {
        $line =~ s/"//g;
        @day = split(/ /,$line);
        $func = shift @day;

        if ($func =~ /^Initiated|^Execution/) {

            if ($day[2] =~/on/) {
                chomp($log);
                print "\n$log,$day[3],$day[1],";
                print $LogDate "\n$log,$day[3],$day[1],";
            }

            if ($day[2] =~ /terminated/) {
                print "$day[5]";
                print $LogDate "$day[5]";
            }
        }
    }

    close($LogDate);

    open(DATA,"LogDate.txt");
        @file = <DATA>;
    close(DATA);

    foreach $line (@file) {
        chomp($line);
        @array = split(/,/,$line);

########## This is where the problem was ##########
        if (length $array[3]) {
            # do nothing
        } 
        else {
            $array[3] = '00:00:00';
        }
##################################################

        $dbh->do("INSERT INTO tblLogDate (Log,Dte,Start,Stop)values('$
+array[0]','$array[1]','$array[2]','$array[3]')");

    }

    $dbh->disconnect;

    exit
}
[download]

#!/usr/bin/perl

use vars qw(@day);

$day[5] = '';
printday();
$day[5]="\n";
printday();
$day[5]=undef;
printday();

sub printday
{
  my $len = length($day[5]);
  if ($len =~ /8/) {
    print "$day[5]";
  } else {
    print "00:00:00";
  }
  print "\n";
}
[download]

00:00:00
00:00:00
00:00:00

Using $len =~ /8/ to see if the length is 8 is very strange. It says "if the string representation of the length contains the digit 8", so will match 8, 18, 3008, 8000000, etc. You probably just want $len == 8.

Thank you for your suggestion to check for errors elsewhere in my code. I did that and now it works!

If the value in $day[5] is a string of spaces 8 characters long, that is what will print out. Any chance of that happening?

A little more code would have been helpful.

print (($day[5] =~ /^\d{2}:\d{2}:\d{2}$/) ? $day[5] : '00:00:00');
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