case, new column not found

I'm trying somethings here and I get strange errors:

select *,(
(CASE WHEN titulo LIKE '%Matematica%' THEN 1 ELSE 0 END) +
(CASE WHEN descripcion LIKE '%Matematica%' THEN 1 ELSE 0 END) +
(CASE WHEN incumbencia LIKE '%Matematica%' THEN 1 ELSE 0 END) )
AS encontrados
FROM admin_view
WHERE admin_view.nivel=1 AND encontrados > 0;

ERROR: Attribute 'encontrados' not found

Why is it? encontrados should be an attribute of type INT with the count of
the rows found.

Any ideas?

Saludos... :-)

--
Cualquiera administra un NT.
Ese es el problema, que cualquiera administre.
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Martin Marques | mmarques(at)unl(dot)edu(dot)ar
Programador, Administrador | Centro de Telematica
Universidad Nacional
del Litoral
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