It sounds like one of the columns in your table has NULL values. Try to add nvl to your SELECT statement, and also try to change
($mb_award,$mb_accept) = $dbh->fetchrow_array();
to two steps -
use Data::Dumper; ... my @res = $dbh->fetchrow_array(); print Dumper(@res); $mb_award = $res[0]; $mb_accept = $res[1];
Use the Data::Dumper module to investigate your variables - I suspect you will see an undef in @res (because one of the column might be NULL).

One last observation is that your test of greater than "0.00" does not work if both values are equal to "0.00" or one is "0.00" and the other is NULL. In other words, the test is incomplete. Perhaps you need to add some exception handling...

if ($mb_award > 0) { $mb_amount_disp = $mb_award; } elsif ($mb_accept > 0) { $mb_amount_disp = $mb_accept; } else { # both values are <= 0 or undef, what shall I do? .... }

In reply to Re: (3) DBI compare columns problem by Roger
in thread DBI compare columns problem by th3monk3y

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.