To learn SQL from basics I have uploaded all the related files in Github and the link is provided below.

The following topics are covered:-

1)DDL

2)DML

3)DCL

4)TCL

5)Keys

6)Relational Schema

7)Data Types

8)Constraints

9)Operators

10)WildCard Characters

11)Aggregate Functions

12)GROUP BY, ORDER BY

13)WHERE (vs) HAVING

14)LIMIT

15)JOINS

16)UNION (vs) UNION ALL

17)SubQueries

18)EXISTS (vs) IN

19)Views

20)Stored Routines

21)Advanced SQL Topics like Triggers, Variables, INDEX, CASE etc

Link to access all the related files:
https://github.com/ruthvikraja/SQL