SQL tutorial: https://tutorial.techaltum.com/SQLServer.html
- SQl subquery: https://www.dofactory.com/sql/subquery
- SQL Query Questions and Answers for Practice: http://www.complexsql.com/sql-query-questions-and-answers-for-practice/
- Database/SQL Interview Questions: https://www.programmerinterview.com/index.php/database-sql/introduction/
- 50 SQL Query Questions And Answers For Practice: https://www.techbeamers.com/sql-query-questions-answers-for-practice/
- 35 Essential Basic-Advanced SQL Query-Questions Asked In Technical Interviews: https://www.c-sharpcorner.com/article/most-asked-sql-queries-in-interview-questions/
- Top 90 Most Popular SQL Interview Questions and Answers: https://www.softwaretestinghelp.com/50-popular-sql-interview-questions-for-testers/
- 45 Essential SQL Interview Questions: https://www.toptal.com/sql/interview-questions
- Top 50 SQL Interview Questions & Answers: https://www.guru99.com/sql-interview-questions-answers.html
- Some-complex-SQL-Queries-and-solution: https://github.com/santoshmungle/Some-complex-SQL-Queries-and-solution
- https://github.com/MaximAbramchuck/awesome-interview-questions#sql
- https://github.com/chetansomani/SQL-Interview-Questions/blob/master/SqlServerInterviewQuestions
- SQL Exercises, Practice, Solution: https://www.w3resource.com/sql-exercises/
- hackerrank sql: https://www.hackerrank.com/domains/sql
- sqlzoo: http://sqlzoo.net/ https://en.wikibooks.org/wiki/SQL_Exercises
- SQL Query Interview Questions: https://www.youtube.com/watch?v=uAWWhEA57bE&list=PLE9641s46IMHBQ6k3tJN5Hc23T3hkXd8H&index=2&t=532s
- Doing Advanced Queries - MySQL Course: https://www.youtube.com/watch?v=es_t9QXpXY4&index=2&list=PLE9641s46IMHBQ6k3tJN5Hc23T3hkXd8H
- Introduction to Databases - Stanford: https://www.youtube.com/playlist?list=PLroEs25KGvwzmvIxYHRhoGTz9w8LeXek0
- Database Clinic: MySQL https://www.lynda.com/MySQL-tutorials/Database-Clinic-MySQL/609013-2.html
- Backup and recovery: https://app.pluralsight.com/library/courses/mysql-backup-recovery-fundamentals/table-of-contents
- Connection pool: https://en.wikipedia.org/wiki/Connection_pool
- MySQL Indexing for Performance: https://app.pluralsight.com/library/courses/mysql-indexing-performance/table-of-contents
- MySQL Query Optimization and Performance Tuning: https://app.pluralsight.com/library/courses/mysql-query-optimization-performance-tuning/table-of-contents
- system design - database scaling: https://github.com/donnemartin/system-design-primer#database
- Scaling Databases - Web Development: https://www.youtube.com/watch?v=dkhOZOmV7Fo
- Sharding and Scaling Your Database: https://www.youtube.com/watch?v=p3ytSdUQZzA
- NoSQL vs SQL: a Database Tutorial - Differences and advantages of NoSQL and SQL: https://www.youtube.com/watch?v=Jt_w2swkXAk
- SQL vs NoSQL or MySQL vs MongoDB: https://www.youtube.com/watch?v=ZS_kXvOeQ5Y
it's so cool. Thank you