4
In phpMyAdmin, after selecting your XOOPS database, select the SQL tab on the right, and then paste in and execute one of the above queries.
Then you can copy/paste the output to a text file.
You can add a limit-clause to the query to control how many rows of output are displayed per page. For example, this would display up to 1000 rows on one page:
SELECT uname FROM xoops_users ORDER BY uname LIMIT 1000