INFO20003 Database Systems
Dr Renata Borovica-Gajic Dr
INFO20003 Database Systems
Copyright By PowCoder代写 加微信 powcoder
Assignment 1
• Due this Friday 01/04 6pm • Two submissions:
1. PDF with conceptual ER model Chen +
Photo of physical model in Workbench (see next page) + Assumptions (if you have them)
2. mwb with the physical model (checking only if your PDF is illegible
• Name them student_id.pdf and student_id.mwb
INFO20003 Database Systems 2
How can you save your physical model?
INFO20003 Database Systems 3
A couple of notes on modeling
• When doing modeling – you are focusing on model of the data (which values we will store)
• Control happens at the application level
–E.g. Medicare: organ donor older than 16
•Only need to know the age of patient (model captures only age •Then we can check whether a donor is older than 16
–How do I create lists?
•Your model needs to capture data (not lists as data structures)
• Why do we provide business requirements and how do you check them?
•No need to provide SQL or anything similar
•This is just for you to help you test your solution, and see whether all required data is available in the model
INFO20003 Database Systems 4
Quiz 3 walkthrough
On the LMS…
INFO20003 Database Systems 5
Homework solutions
(𝐵𝐵𝑆𝑆𝑆𝑆𝐵𝐵𝑆𝑆 𝑅𝑅𝑅𝑅𝑆𝑆𝑅𝑅𝑆𝑆𝑅𝑅𝑅𝑅𝑆𝑆)
𝜋𝜋𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠(𝜎𝜎𝑟𝑟𝑠𝑠𝑟𝑟𝑟𝑟𝑠𝑠𝑟𝑟>9(𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆))
𝜋𝜋 (𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 𝜎𝜎 (𝑅𝑅𝑅𝑅𝑆𝑆𝑅𝑅𝑆𝑆𝑅𝑅𝑅𝑅𝑆𝑆)) 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑑𝑑𝑠𝑠𝑑𝑑<"11/01/96"
1. Find the name of all sailors whose rating is above 9
2. Find all sailors who reserved a boat prior to November 1, 1996
Find (the names of) all boats that have been reserved at least once
𝑏𝑏𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠
INFO20003 Database Systems 6
Homework solutions
4. Find all pairs of sailors with the same rating
𝜌𝜌(𝑆𝑆𝑆 𝑆 → 𝑆𝑆𝑆𝑆𝑠𝑠𝑆, 𝑆 → 𝑆𝑆𝑠𝑠𝑆𝑆𝑠𝑠𝑅𝑅𝑆, 3 → 𝑆𝑆𝑆𝑆𝐵𝐵𝑆𝑆𝑠𝑠𝑟𝑟𝑆,4 → 𝑆𝑆𝑟𝑟𝑅𝑅𝑆 , 𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆) 𝜌𝜌(𝑆𝑆𝑆 𝑆 → 𝑆𝑆𝑆𝑆𝑠𝑠𝑆, 𝑆 → 𝑆𝑆𝑠𝑠𝑆𝑆𝑠𝑠𝑅𝑅𝑆, 3 → 𝑆𝑆𝑆𝑆𝐵𝐵𝑆𝑆𝑠𝑠𝑟𝑟𝑆,4 → 𝑆𝑆𝑟𝑟𝑅𝑅𝑆 , 𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆)
𝜋𝜋𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠1,𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑆𝑆𝑆 𝑟𝑟𝑠𝑠𝑟𝑟𝑟𝑟𝑠𝑠𝑟𝑟1=𝑟𝑟𝑠𝑠𝑟𝑟𝑟𝑟𝑠𝑠𝑟𝑟𝑠 𝑠𝑠𝑟𝑟𝑑𝑑1!=𝑠𝑠𝑟𝑟𝑑𝑑𝑠 𝑆𝑆𝑆
INFO20003 Database Systems 7
Let’s test our understanding
•Please go to: PollEv.com/rbor
INFO20003 Database Systems 8
程序代写 CS代考 加微信: powcoder QQ: 1823890830 Email: powcoder@163.com