I would also recommend something like HTML::Template (or Template Toolkit) if you want to do some complex calculations/checking. But some of this can be done in SSI pretty simply. e.g.: 
<A HREF='http://affiliateprogram.com?id=<!--#if expr="$QUERY_STRING" -
+-><!--#echo var="QUERY_STRING" --><!--#else -->50<!--#endif -->">Link
+</A>

[download]
You can also use SSI to check to make sure that the query string matches a specific regular expression, etc. See http://httpd.apache.org/docs/mod/mod_include.html for more info.

In reply to Re: Speed consideration by koolade
in thread Speed consideration by SpaceAce

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