I made a mistake in typing with a new text editor 0E0 got typed as 0EO, this still does work.

Anyway a useful thing to know, albeit embarrassing for me due to the typo. There is such a thing as "True" but numerically false!

The DBI returns "0E0" for the "true but zero" value. It does that when the query succeed but returned no rows. I haven't been writing Perl for awhile, so I seek guidance about how to handle this in recent Perl versions? There appears to be an extraneous warning when using arithmetic with a number represented as an exponential string. 

#!/usr/bin/perl
use warnings;
use strict;
$|=1;


print "**TrueZeroValue = $TrueZeroValue\n";

if ($TrueZeroValue)
{
   print "**This value is True\n";
}

$TrueZeroValue += 0; #this used to have no warnings and 
                     #converted exponential string notation to
                     #a numeric value

if ($TrueZeroValue == 0)
{
   print "**This value is zero numerically\n";
   print "**but with current Perl, a warning happens\n";
}

__END__
**TrueZeroValue = 0EO
**This value is True
Argument "0EO" isn't numeric in addition (+) at C:\Projects_Perl\TrueZ
+eroValue.pl line 14.
**This value is zero numerically
**but with current Perl, a warning happens

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In reply to The True but Zero value? by Marshall

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