यह आपकी क्वेरी है।
SELECT a.name_client,
MAX(CASE WHEN b.status = 'A' THEN c.name_skill END) 'SKILL A',
MAX(CASE WHEN b.status = 'B' THEN c.name_skill END) 'SKILL B'
FROM client a
LEFT JOIN client_skill b ON b.client = a.id_client
LEFT JOIN skill c ON c.id_skill = b.skill
GROUP BY a.id_client
ORDER BY id_client
