Use Case Diagrams : https://www.youtube.com/watch?v=zid-MVo7M-E
ER Diagrams (part 1) : https://www.youtube.com/watch?v=QpdhBUYk7Kk
ER Diagrams (part 2) : https://www.youtube.com/watch?v=-CuY5ADwn24
Use Case Diagrams : https://www.youtube.com/watch?v=zid-MVo7M-E
ER Diagrams (part 1) : https://www.youtube.com/watch?v=QpdhBUYk7Kk
ER Diagrams (part 2) : https://www.youtube.com/watch?v=-CuY5ADwn24