I have the following in my script - 
$coord_{$key1}{$key2}[[2]] = $sth->fetchrow_array;

[download]
where fetchrow_array belongs to DBI

Sometimes though fetchrow_array will not find an entry, so what I want to do is store missing entries in my database as 0 in the corresponding variable. So lets say the corresponding entry for $coord_{"AB"}{5}[[2]] has no entry in the database, then I want $coord_{"AB"}{5}[[2]] = 0 instead of $coord_{"AB"}{5}[[2]] = "uninitialized value";

So I could use something like - 

if($coord_{$key1}{$key2}[2] eq "uninitialized value")
{
  $coord_{$key1}{$key2}[2] = 0;
}

[download]
but how does perl represent this "uninitialized value" that I'm using above? I hope that makes sense.

Thanks
Barry.

In reply to use of uninitialized values by Baz

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