WHY IS LEFT JOIN slow?

Related questions

1. What is subquery in SQL with examples?
2. What does exists mean in SQL?
3. Why inner join is faster than LEFT JOIN?
4. Is still an adverb?
5. What is the synonym of continuing?
6. What is the difference between a subquery and a join?
7. What is the difference between not exists and not in in SQL?
8. What's another word for still there?
9. Is subquery better than join?
10. What is the opposite of exist?

Tags

1. #perhaps
2. #looks
3. #query
4. #email
5. #doing
6. #columns
7. #explain
8. #character
9. #compatible
10. #output
11. #collations
12. #inner
13. #collation
14. #because
15. #easily
16. #solution
17. #mysql
18. #change
19. #making
20. #identical
21. #slower
22. #nested