How can optimize query Key in mysql

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In this video, I discussed that Important query of MYSQL Database, this videos complete in Hindi
1-How can optimize the query
2-How can change the query according to requirement
3-This query in already asked in interviews
4-Faru Interviews Question having a lot lot of interviews question related with php and mysql database.
5-Faru Interviews Question 2017 | Interviews crack 1 Review | Video ranking SEO

MYSQL Interview Question-1 : https://www.youtube.com/watch?v=PPG9R4x4Qmw

MYSQL Interview Question-2 : https://www.youtube.com/edit?o=U&video_id=TV4OvfN3zgg

Cake framework Videos-1 : https://www.youtube.com/watch?v=HwYv5YS85y4&t=31s

Cake framework Videos-2 : https://www.youtube.com/watch?v=W0q8RSboNc8&t=1679s

Laravel framework Videos-1 : https://www.youtube.com/watch?v=Oih8qfGGb4Q&t=80s

Laravel framework Videos-2 : https://www.youtube.com/watch?v=L8LiRlJgM7c&t=8s

Create error log file Videos-1 : https://www.youtube.com/watch?v=1O4mbgl3-sY
Page not found Videos-1 : https://www.youtube.com/watch?v=AfE3evCwC70&t=7s

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