query to url

Hi,
Look, such a url:
com_flexicontent&view=category&cid=13
that shows category items for category 13, apparently equals to such query in db:
SELECT i.title
FROM #_content i
RIGHT(LEFT or INNER) JOIN #_flexicontent_cats_item_relations rel ON rel.itemid = i.id
WHERE rel.catid =13

The question is: What's the equal url for this query:
SELECT i.title
FROM #_content i
RIGHT(LEFT or INNER) JOIN #_flexicontent_cats_item_relations rel ON rel.itemid = i.id
WHERE rel.catid =4
?
Or: How can I show such a query in the web? Any suggestions?
*Both categories are assigned to same template.

Thanks
OR rel.catid =13