All I can say is no wonder it took you a while to get the parenthesizing right when you've formatted (or haven't formatted) the query like that. What's wrong with some return characters in there?
my $sql="
SELECT
        idNum,
        (First(price)-Last(price)) AS difference,
        Min(dateCreated) AS minDate,
        Max(dateCreated) AS maxdate,
        Last(mobile) AS lastMobile,
        Last(contents) AS lastContents,
        (( (First(price)-Last(price)) /First(price) )*100) AS percentC
+hange,
        Last(price) AS lastPrice,
        Last(state) AS lastState,
        Last(contact),
        Last(year)
FROM carAdds
GROUP BY idNum
HAVING (( Last([year]))>=$yearmodel)
ORDER BY (( (First(price)-Last(price)) /First(price) )*100) DESC
";

[download]

Doesn't that look better? It'll be much easier to debug and change, and understand for the next guy, too.

In reply to Re: Strange error when .cgi deployed on a different machine by Jasper
in thread Strange error when .cgi deployed on a different machine by sirius98

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.