MySQL 8.0

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CREATE TABLE wp_usermeta
    (`user_id` int, `meta_key` varchar(27), `meta_value` varchar(4))
;
    
INSERT INTO wp_usermeta
    (`user_id`, `meta_key`, `meta_value`)
VALUES
    (2, 'admin-first-timer-training', NULL),
    (2, 'admin-first-timer-overnight', 'No'),
    (2, 'admin-first-timer-outdoor', 'No')
;
SELECT * FROM wp_usermeta wHERE `meta_value` = 'No'


user_id
meta_key
meta_value


2
admin-first-timer-overnight
No

2
admin-first-timer-outdoor
No


SELECT
    `user_id`,
    MIN(CASE WHEN `meta_key` = 'admin-first-timer-training' AND `meta_value` = 'No' THEn 'No' ELSE 'Yes' END) as 'admin-first-timer-training',
    MIN(CASE WHEN `meta_key` = 'admin-first-timer-overnight' AND `meta_value` = 'No' THEn 'No' ELSE 'Yes' END) as 'admin-first-timer-overnight',
   MIN(CASE WHEN `meta_key` = 'admin-first-timer-outdoor' AND `meta_value` = 'No' THEn 'No' ELSE 'Yes'  END) as 'admin-first-timer-outdoor'
FROM wp_usermeta
GROUP BY user_id


user_id
admin-first-timer-training
admin-first-timer-overnight
admin-first-timer-outdoor


2
Yes
No
No