From Facebook Developer Wiki

[edit] FQL Example

FQL queries take the form: SELECT <fields> FROM <table> WHERE <conditions>

This example returns all the page_id's that a given user is an admin for:

SELECT page_id FROM page_admin WHERE uid = <uid>

1181029451 09:08, 10 November 2008 (PST)

Unfortunately Facebook doesn't allow us to rab all uids based on a page_id