I don't see any obvious problems, but I would make your script produce more verbose output so it is clear what is going on (at least for debugging purposes): 
open(FILE, "<", "mahi.txt") or die "Unable to open mahi.txt: $!";
while (<FILE>) {
  chomp;
  print "Looking up PART_NUMBER: >$_<\n";
  $sth->execute($_) or die "execute failed: ".$sth->errstr;
  my ($dup) = $sth->fetchrow_array();
  print "  Query returned: >$dup<\n";
  if ($dup eq $_) {
    print "  PART_NUMBER $_ is present\n";
  } else {
    print "  Failed to locate PART_NUMBER >$_<\n";
  }
}

[download]
If you run this script perhaps it will tell you more about what is failing.

In reply to Re: error in sql query while using DBI by pc88mxer
in thread error in sql query while using DBI by mahicool

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