Class XII Chapter 09 : More on databases and SQL
https://drive.google.com/file/d/0BxdixE-ge8NUa1BwQ1U4Y1NGdE0/view?usp=sharing
Class XII Chapter 10 : Advanced RDBMS Concepts
https://drive.google.com/file/d/0BxdixE-ge8NUel9ZWHRWY3NSS3M/view?usp=sharing
https://drive.google.com/file/d/0BxdixE-ge8NUa1BwQ1U4Y1NGdE0/view?usp=sharing
Class XII Chapter 10 : Advanced RDBMS Concepts
https://drive.google.com/file/d/0BxdixE-ge8NUel9ZWHRWY3NSS3M/view?usp=sharing