[Zope] dtml-if question

[Kyroraz]

Hello,

I am looking to search a SQL database for variables that may have been 
passed by a webform.  Basically, when a user submits a userform, there 
are checkboxes that can or cannot be checked, and I would like to check 
the results back for the existance of these variables against the SQL 
database.  An example would be...

<dtml-in sql_method_that_returns_all_values>
<dtml-if <dtml-var 
important_column_that_may_exist_also_as_a_passed_variable> >
   Yes, this was passed.
<dtml-else>
   No, it wasn't passed
</dtml-if>

This is the logic that I am seeking, but I get a syntax error every time 
I try this.  Does anyone out there have any suggestions?

Jason