What would the difference between these two queries be? They yield the same results.
SELECT * 
FROM Person 
JOIN Worker 
  ON Person.id = Worker.id;
and
SELECT * 
FROM Person, 
     Worker 
WHERE Person.id = Worker.id;
There is no difference at all.
https://stackoverflow.com/questions/20138355/whats-the-difference-between-comma-separated-joins-and-join-on-syntax-in-mysql
 
				 수신 기한이 지난 데이터를 MySQL에서 삭제할 때의 이야기
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