[Kaperstone]

(Untested)

Select or Insert ( https://dev.mysql.com/doc/refman/5.7...functions.html , https://dev.mysql.com/doc/refman/5.7/en/case.html )

Код:

SELECT CASE WHEN (SELECT COUNT(*) FROM player_stats WHERE id = 5 LIMIT 1)>0 
THEN 
    (SELECT * FROM player_stats WHERE id = 5 LIMIT 1) 
ELSE        
    INSERT INTO player_stats (id, name, etc) VALUES (1, 'Meller', 'etc etc')
END

Insert if not exists ( https://dev.mysql.com/doc/refman/5.7...ubqueries.html )

Код:

INSERT INTO player_stats (id, name, etc)
SELECT * FROM (SELECT 'Meller', 'etc etc') AS tmp
WHERE NOT EXISTS (
    SELECT * FROM player_stats WHERE id = 5 LIMIT 1)
) LIMIT 1;

I am not sure whether it will cause mysql errors, but you can search on ****** for some answers or explore the MySQL documentation.

There is also INSERT ... ON DUPLICATE KEY UPDATE