it consists of SQL queries for each topic in SQL.

Reference for learning:

https://www.w3schools.com/sql/

SQL Basics Tutorial For Beginners: https://youtube.com/playlist?list=PLUaB-1hjhk8GT6N5ne2qpf603sF26m2PW

Intermediate SQL Tutorial: https://youtube.com/playlist?list=PLUaB-1hjhk8HTgPnBukmMq7QTe83ANirL

Advanced SQL Tutorials: https://youtube.com/playlist?list=PLUaB-1hjhk8EBZNL4nx4Otoa5Wb--rEpU

Learn Complete SQL (Beginner to Advance): https://youtube.com/playlist?list=PLavw5C92dz9Ef4E-1Zi9KfCTXS_IN8gXZ