Sim, você pode usar estas queries para listar os usuários do OpenLMS seguindo estas instruções

Listando usuários ativos

SELECT COUNT(DISTINCT u.id) AS usuarios_con_acceso
FROM mdl_user u
JOIN mdl_role_assignments ra ON ra.userid = u.id
JOIN mdl_context ctx ON ra.contextid = ctx.id
JOIN mdl_course c ON c.id = ctx.instanceid
JOIN mdl_role r ON ra.roleid = r.id
WHERE u.deleted = 0
AND u.suspended = 0
AND u.confirmed = 1
AND c.visible = 1
AND ctx.contextlevel = 50
AND r.archetype IN ('student', 'teacher', 'editingteacher')

Listando usuários totais

SELECT COUNT(*) AS total_usuarios
FROM mdl_user

Listando usuários disponíveis (que podem fazer login)

SELECT COUNT(*) AS usuarios_con_capacidad_de_logueo
FROM mdl_user
WHERE deleted = 0
AND suspended = 0
AND confirmed = 1