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| author | mo khan <mo.khan@gmail.com> | 2020-01-21 19:30:45 -0700 |
|---|---|---|
| committer | mo khan <mo.khan@gmail.com> | 2020-01-21 19:30:45 -0700 |
| commit | 2a96a1ccbfb8da1f87391903a50420fd8e6d2f60 (patch) | |
| tree | 92cf3bb1d15c810ef5f28aeaeb0faf98241e9f21 /assignments | |
| parent | 0b357a1e285ecce30f27ef477fbf5b63834fcdd7 (diff) | |
Format assignment 2
Diffstat (limited to 'assignments')
| -rw-r--r-- | assignments/2/README.md | 71 |
1 files changed, 38 insertions, 33 deletions
diff --git a/assignments/2/README.md b/assignments/2/README.md index a22dabc..deaa85e 100644 --- a/assignments/2/README.md +++ b/assignments/2/README.md @@ -5,67 +5,72 @@ Weight: 15% of your final grade Due: After you have completed Unit 6. Answer all of the following questions, and upload your completed work here. -Question 1 (12 marks) + +## Question 1 (12 marks) Consider the following EER diagram for the Royal Victoria Hospital (RVH) database. + EER Diagram Data volume and access for this diagram are as follows: - There are 1 000 patients and 500 items yielding a total of 10 000 usage records in the database. - There are 50 physicians and a total of 4 000 prescriptions in the database. - There are 200 treatments in the database. - There are 50 accesses per day for patient records; of these, 30 request access to both prescription and usage records. - There are 20 accesses per day for physician records; of these, 20 request access to prescriptions. - There are 50 accesses per day to item records; of these, 10 request access to usage records. - There are 5 direct accesses per day for treatment records. - Of the total accesses to prescription records, 20 request access to patients, 30 request access to physicians, and 35 request access to treatment. - Of the total accesses to usage records, 10 request access to patients and 30 request access to items. +* There are 1 000 patients and 500 items yielding a total of 10 000 usage records in the database. +* There are 50 physicians and a total of 4 000 prescriptions in the database. +* There are 200 treatments in the database. +* There are 50 accesses per day for patient records; of these, 30 request access to both prescription and usage records. +* There are 20 accesses per day for physician records; of these, 20 request access to prescriptions. +* There are 50 accesses per day to item records; of these, 10 request access to usage records. +* There are 5 direct accesses per day for treatment records. +* Of the total accesses to prescription records, 20 request access to patients, 30 request access to physicians, and 35 request access to treatment. +* Of the total accesses to usage records, 10 request access to patients and 30 request access to items. Draw a composite usage map for the RVH database. -Question 2 (12 marks) + +## Question 2 (12 marks) Answer the following questions (250 words max/question). - What are the typical integrity controls performed in both data integrity and referential integrity? - Using an example for each situation, illustrate the three common situations that suggest relations should be denormalized. - What are the advantages and disadvantages of horizontal and vertical partitioning? +* What are the typical integrity controls performed in both data integrity and referential integrity? +* Using an example for each situation, illustrate the three common situations that suggest relations should be denormalized. +* What are the advantages and disadvantages of horizontal and vertical partitioning? -Question 3 (12 marks) +## Question 3 (12 marks) Answer the following questions (250 words max/question). - What factors should be considered when choosing a file organization? - What is the purpose of clustering data in a file? - Compare hashed file organization versus indexed file organization. List two advantages of indexed over hashed, and two advantages of hashed over indexed. +* What factors should be considered when choosing a file organization? +* What is the purpose of clustering data in a file? +* Compare hashed file organization versus indexed file organization. List two advantages of indexed over hashed, and two advantages of hashed over indexed. -Question 4 (18 marks) +## Question 4 (18 marks) Consider the following database: Employee(emp-no, name, department, salary), ProjAssigned(emp-no, proj-no, worked-hours) - Write one SELECT SQL query to list the numbers and names of all employees with a salary greater than 66 000 who are assigned to projects, the projects they are assigned to, and the corresponding hours worked. Your list should be sorted by employee name. - Define indexes on selected attributes to speed up your query, and justify your selections. - Write SQL queries to create the indexes you defined above. +* Write one SELECT SQL query to list the numbers and names of all employees with a salary greater than 66 000 who are assigned to projects, the projects they are assigned to, and the corresponding hours worked. Your list should be sorted by employee name. +* Define indexes on selected attributes to speed up your query, and justify your selections. +* Write SQL queries to create the indexes you defined above. -Question 5 (40 marks) +## Question 5 (40 marks) Consider the following three relations: +```text TRAVEL_AGENT (name, age, salary) CUSTOMER (name, departure_city, destination, journey_class) TRANSACTION (number, cust_name, travel_agent_name, amount_paid) +``` Write SQL statements to answer the following questions. - Compute the number of different customers who have a transaction. - Display the name of the oldest travel agent. - List the total number of transactions for each travel agent. Consider only those transactions where the amount paid exceeds 1 000. - Display the names and ages of the travel agents who have arranged journeys for customer “John Smith”, in descending order of age (use a subquery). - Display the names and ages of travel agents who have arranged journeys for customer “John Smith”, in descending order of age (do not use a subquery). - Display the age of travel agents who have arranged journeys for customer “John Smith” to “Ottawa” (use a subquery). - Display the age of travel agents who have arranged journeys for customer “John Smith” to “Ottawa” (do not use a subquery). - Display the names and salaries of all travel agents who did not arrange journeys for customer “John Smith”, in ascending order of salary. - Display the names of travel agents who have five or more transactions. - Display the names of all travel agents who have arranged at least ten journeys to “Ottawa”. +* Compute the number of different customers who have a transaction. +* Display the name of the oldest travel agent. +* List the total number of transactions for each travel agent. Consider only those transactions where the amount paid exceeds 1 000. +* Display the names and ages of the travel agents who have arranged journeys for customer “John Smith”, in descending order of age (use a subquery). +* Display the names and ages of travel agents who have arranged journeys for customer “John Smith”, in descending order of age (do not use a subquery). +* Display the age of travel agents who have arranged journeys for customer “John Smith” to “Ottawa” (use a subquery). +* Display the age of travel agents who have arranged journeys for customer “John Smith” to “Ottawa” (do not use a subquery). +* Display the names and salaries of all travel agents who did not arrange journeys for customer “John Smith”, in ascending order of salary. +* Display the names of travel agents who have five or more transactions. +* Display the names of all travel agents who have arranged at least ten journeys to “Ottawa”. |
