Here is a query that will show you the pages in your wiki that contain a particular string. In this example, I wanted to find all pages that were using the 'Icon' extension parser extension magic word '#icon'.
<source lang="sql">
WHERE rev_text_id
IN (
SELECT old_id FROM `text` WHERE old_text LIKE '%#icon%'
)
</source>
== See Also ==
* [[mw:Manual:Database_access]]
[[Category:Database]]
[[Category:Wiki]]
[[Category:Development]]
[[Category:Help]]