2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 1/40 ISYS2120 Semester 2, 2020 Final Exam Started: Dec 9 at 17:00 Quiz Instructions Important Notes: If you have trouble seeing images in your browser refer to images in this pdf file Final_Exam_Figures.pdf Answer ALL questions. The duration for this exam is 130 minutes. Writing time 120 minutes and reading time 10 minutes. At the end of the exam, submit your answers by clicking the "Submit Quiz" button at the bottom. You are only given ONE attempt to submit your answers. Once you have finished with the quiz, make sure you submit your handwritten notes to the Assignment Do NOT click "Submit Quiz" until you have completed the exam. Section 1 0.5 ptsQuestion 1 The number of other relations it is associated with The number of columns it has The maximum number of rows it can have The number of rows it has What does the cardinality of a relation refer to? 0.5 ptsQuestion 2 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 2/40 A set of attributes that refers to the candidate key of a parent relation. A minimal set of attributes in a relation that can uniquely identify each row of that relation. The key of an index that is used to speed up response to user queries. A set of attributes in a relation that can uniquely identify each row of that relation. Which of the following most precisely describes a candidate key for a relation? 0.5 ptsQuestion 3 True False Unknown In three valued logic, the result of ((NULL > 8) AND (UNKNOWN OR TRUE)) is: 0.5 ptsQuestion 4 removes unwanted columns from a relation allows us to rename a field or operation selects a subset of rows from a relation selects a subset of columns from a relation Choose the answer which most accurately describes the relational algebra selection operator from the following: 1 ptsQuestion 5 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 3/40 count(name is null) count(*) count(*) - count(distinct name) count(*) - count(name) Relation R contains a primary key attribute called "pid", and another nullable attribute called "name". If you wanted to count the number of rows in relation R where name is null, which of the following count operators and arguments would you use? 1 ptsQuestion 6 True False In the query clause evaluation order of a single query with no subqueries, the HAVING clause is always run before the WHERE clause. 1 ptsQuestion 7 Transient Correlated Lossless Dependency-preserving A decomposition of R into S and T is _________________________________ if all Functional Dependencies that were given to hold on R must hold on S and/or T. 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 4/40 1 ptsQuestion 8 For all non-trivial X --> Y for R: (X is either a superkey of R) OR (Y is part of a key in R) Prohibition of trivial dependencies X --> Y where Y is part of a key. Prohibition of non-trivial dependencies X --> Y where Y is a strict (proper) subset of a foreign key For all non-trivial X --> Y for R: X is a superkey for R For a relation R, which of the following most accurately describes the condition that needs to hold for Boyce-Codd Normal Form: 1 ptsQuestion 9 Clustering a table with an index makes finding and retrieving a single record faster A table must have at least one index A table can have multiple clustered indexes Clustering a table with an index can make range searches faster Which of these statements is true? 1 ptsQuestion 10 CREATE USER GRANT REVOKE CREATE LOGIN To realize the effect of discretionary access control at DBMS level, which command(s) shall be used? 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 5/40 1 ptsQuestion 11 Efficiency User Interaction Security Correctness Which of the following is/are NOT feature(s) of stored procedures? 1 ptsQuestion 12 The mechanism is supposed to introduce a random string to each password after hashing. A secure hash function should always be in place. Salting of hashed passwords is an ideal solution to password security. The hashing function is usually one-way that cannot transform the hashed passwords to their original form. End users can create passwords of their own, which should be transformed by a set algorithm. Which of the following is/are NOT true about password security? 1 ptsQuestion 13 Which of the following is/are unstructured data? 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 6/40 Text documents Video Images Excel spreadsheets Relational tables Audio files 1 ptsQuestion 14 Data minimalism Authorization Data privacy Authentification In order to ensure database security, every connection must login with an identifying username or e-mail address and a password. What is the security mechanism this practice is using at the DBMS level? 1 ptsQuestion 15 Relations Entities Properties of entities Identifying relationships Weak entities What are the comprising elements of a knowledge graph? 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 7/40 1 ptsQuestion 16 Ontologies can be used for text data. It is more flexible than conceptual modeling of relational databases. A knowledge graph can be realized by integrating one or more ontologies. It is a schema-first approach. Which of the following is/are NOT true about ontologies? 3 ptsQuestion 17 Consider the following relational database schema and example database instance (primary keys are underlined; foreign keys are in italic, referring to the same attribute in a different table): Airlines (aid, airline, country) Passengers(pid, name, address) Bookings (bid, aid, pid, date, flight, destination, price) Airlines aid airline country QFA Qantas Australia SIA Singapore Airlines Singapore Passengers pid name country 1 Stephen Fry UK 2 Michael Jordon USA 3 Hugh Jackman AU Bookings 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 8/40 (UK, 1, 3000) (AU, 2, 2000) (UK, 1, 3000) (NULL,1,2500) (AU, 2, 2000) (UK, 1, 3000) (AU, 2, 4000) (UK, 1, 3000) (USA,1,2000) (AU, 3, 2000) bid aid pid date flight seat price 1001 QFA 1 05.05.2020 QF 129 A15 3000 1002 QFA 3 05.05.2020 QF 129 C23 2000 1003 QFA NULL 05.05.2020 QF 129 NULL 2500 1004 QFA 3 05.05.2020 QF 129 G65 NULL 1005 SIA 1 15.05.2020 SQ 38 H42 2000 What is the output of the following SQL query on the given example database instance? SELECT P.country, COUNT(B.seat), SUM(B.price) FROM Bookings B, Passengers P, WHERE B.pid = P.pid AND B.flight = 'QF 129' GROUP BY P.country; 1 ptsQuestion 18 Consider the following relational database schema (primary keys are underlined; foreign keys are in italic, referring to the same attribute in a different table): Airlines (aid, airline, country) Passengers(pid, name, address) Bookings (bid, aid, pid, date, flight, seat, price) 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 9/40 Finish the following SQL query such that it identifies all bookings with an unknown price. SELECT B.bid, P.name, B.flight FROM Bookings B [ Select ] Passengers P WHERE [ Select ] 1 ptsQuestion 19 A B+-tree index on Movie(length) A hash index on Movie(length) A bitmap index on Movie(length) A B+-tree index on (FilmActor(name), Movie(length, rating)) A bitmap index on Movie(rating) Which of the following indexes would you choose to create to improve the runtime of the following SQL query that lists all actors of long movies with a rating of 5? You can create more than one index. SELECT A.name FROM Film_Actor A JOIN Movie M ON (A.plays_in = M.movie_id ) WHERE M.length > 120 AND M.rating = 5; 1 ptsQuestion 20 Which one of the following indexes would you choose to create to improve the runtime of the following SQL query that finds the names of all restaurants which 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 10/40 A GiST/R+-tree index on Restaurants.location A GiST/R+-tree index on Neighbourhoods.geom A bitmap index on Neighbourhoods.name A B+-tree index on (Neighbourhoods.geom, Restaurants.location) A B+-tree index on (Restaurants.name, Neighbourhoods.geom, Restaurants.location) are located in the Inner West neighbourhood? SELECT R.name FROM Restaurants R, Neighbourhoods N WHERE ST_Contains(N.geom, R.location) = True AND N.name = 'Inner West'; 1 ptsQuestion 21 Role, Secrecy View, Availability Role, Availability View, Secrecy Consider a Supermarket database has a table named Customer. The Customer table defined as Customer(customer_id, customer_name, email, phone, address, birthday). When a customer wants to apply a special discount, the checkout staff need only check the name and birthday of the customer instead all of them. To protect customer’s privacy, the manager decided to create a new ________ to present customer_id and birthday for checkout staffs. Therefore, all checkout staff can only see customer_id and birthday. It guarantees ______. 1 ptsQuestion 22 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 11/40 INITIALLY IMMEDIATE NOT DEFERRABLE NOT NULL INITIALLY DEFERRED Consider a Bank database has a table named Account. The Account table defined as Account (BSB, Account_name, balance). The account balance will be updated by transactions in the database. The balance in the bank is required to be at least 10,000 dollars or the account will not be available. The constraint should be declared as a ______ checking. 1 ptsQuestion 23 Unique and Not null, Foreign Key Integrity Unique, Referential Integrity Unique, Foreign Key Integrity Unique and Not null, Referential Integrity Consider a company has two tables named Staff and Department. The Staff is defined as Staff(staff_id, name, address, department_id). The Department is defined as Department(department_id, department_name). The department_id in Staff is a foreign key reference to the department_id in the Department table. To maintain Primary Key Constraints, the staff_id and department_id should be ______. To maintain ______, each department_id in the Staff table should have a corresponding one in the Department table 1 ptsQuestion 24 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 12/40 UPDATE, Row-level granularity INSERT, Row-level granularity UPDATE, Statement-level granularity INSERT, Statement-level granularity Consider a Toy Store has a table named Account. The Account table defined as Account (ID, account_name, customer_id, balance). The initial balance is required to be at least 1,000 dollars when a new account is created. The store manager wants to implement a Trigger to maintain this constraint. Therefore, the trigger should be specific to ______ event and the granularity of the trigger is _______ 1 ptsQuestion 25 For the following SQL statements choose whether they fit the mold of OLTP or OLAP. 1. BEGIN; UPDATE accounts SET balance = balance - 10000 WHERE name= ‘WOTC’; UPDATE accounts SET balance = balance + 10000 WHERE name=’Harshana’; COMMIT; 2. SELECT country, COUNT(brand) FROM Sales A JOIN Date D USING (date_id) JOIN Store S USING (store_id) JOIN Product P USING (product_id) WHERE D.year BETWEEN 2000 AND 2010 AND P.category =’movies’ GROUP BY country HAVING SUM(A.units_sold) > 1000000 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 13/40 1 [ Select ] 2 [ Select ] 1 ptsQuestion 26 Data warehouses are the most suitable solution for storing huge datasets for extended amounts of time One system should be used for OLTP and OLAP if both processing types use the same dataset. Data warehouses are not updated incrementally as this can result in the database being in an inconsistent state. Data warehouses can accomodate data generated by or required for both OLTP and OLAP respectively. Which of the following statements on data warehousing is/are true? Multiple solutions are allowed. 1 ptsQuestion 27 Given a star schema where we have one fact table sales, and four dimension tables: Time, Customer, Store and Product. Which dimension of the data cube does the following query aggregate over? SELECT S.Product_Id SUM(S.total_sales) FROM SALES S WHERE time_id =’T1’ GROUP BY S.Product_id,S.Time_id, S.Customer_id 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 14/40 Customer Time Product Store Sales 1 ptsQuestion 28 The state of the database will always return to the state before the transaction started. It is possible that the state of the database can return to a point within the transaction. All the operations reached before the transaction aborts will be committed. There is no guarantee as to what operations within the transaction will be committed. Given a database with a guarrantee of atomicity, when a transaction aborts which of the following is True? 1 ptsQuestion 29 Given an ISA hierarchy with entity A three lower-level entity sets B, C and D, which of the following constraints will satisfy these properties: 1. A must belong to one of the lower level entity sets 2. A can belong to multiple lower level entity sets [ Select ] Overlap/key constraint and [ Select ] covering/participation constraint. 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 15/40 1 ptsQuestion 30 A Candidate key is a minimal superkey A composite primary key can have one of the component attributes be NULL If the closure of an attribute set X has a result set that includes all attributes in a relation, then X is a candidate key A part of a Candidate key can have a null value Which of the following statements is/are False: Multiple answers allowed for this question. Section 2 1 pts HTML Editor Question 31 Suppose we have a table R with a column D which is declared as FOREIGN KEY REFERENCES S(id) ON UPDATE CASCADE Suppose we want to change the value of D in some row in R to some arbitrary value X. What would happen? 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 16/40 0 words 1 ptsQuestion 32 Given the following query how many queries are required to obtain the same solution without the use of CUBE or ROLLBACK? SELECT S.Time_id, S.Product_id, S.Store_id, SUM(S.total_sales) FROM Sales S GROUP BY CUBE(S.Time_id, S.Product_id, S.Store_id) 6 ptsQuestion 33 A reservation system keeps track of flight reservations using the following schema: 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 17/40 Airline(airlineID, name, country) Passenger(passengerID, name, address) Booking(bookingID, passengerID, airlineID, bookingDate) FlightLeg(bookingID, flightCode, fareType, price, seat) The first two tables are self-explanatory. Each tuple in Booking describes a booking made by a particular passenger with a particular airline. A booking can consist of several separate flights (‘legs’), which are stored in the last relation, FlightLeg. This table describes which flights have been booked per booking, at what price and (optionally) which seat has been allocated. For example, a booking of passenger ‘4711’ with Qantas for a return flight between Sydney and Melbourne (using flights QF409 and QF450) could have these rows in Booking and FlightLeg tables: Booking(1234, 4711, ‘Qantas’, 2021-05-31); FlightLeg(1234, ‘QF409’, ‘economy’, 163, ‘23C’); FlightLeg(1234, ‘QF450’, ‘business’, 560, NULL); Part A [4 marks] Write a Relational Algebra expression that retrieves the fareType and bookingDate for all flight reservations that have the ‘QF370’ flight code. As you cannot type the usual RA Greek letters easily, you should use the following convention. Operator parameters should be enclosed in square brackets. 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 18/40 HTML Editor Part B [2 marks] Look at the following two SQL queries: Q1: SELECT A.name FROM Airline A, Booking B WHERE A.airlineID = B.airlineID; Q2: SELECT A.name FROM Airline A WHERE A.airlineID IN (SELECT B.airlineID FROM Booking B); Although these queries Q1 and Q2 seem to be essentially the same, they actually can produce different sets of results. How could these results sets differ? What change could you make to Q1 to produce the same set of tuples as Q2? 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 19/40 0 words 2 pts HTML Editor Question 34 This question is based on the same schema discussed in Q32. Airline(airlineID, name, country) Passenger(passengerID, name, address) Booking(bookingID, passengerID, airlineID, bookingDate) FlightLeg(bookingID, flightCode, fareType, price, seat) Write an SQL query to find name of all passengers who made only one booking with ‘Qantas’ airline 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 20/40 0 words 2 pts HTML Editor Question 35 This question is based on the same schema as discussed in Q32. Airline(airlineID, name, country) Passenger(passengerID, name, address) Booking(bookingID, passengerID, airlineID, bookingDate) FlightLeg(bookingID, flightCode, fareType, price, seat) Write an SQL query to find the maximum fare of each flightCode starts with ‘QF’. 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 21/40 0 words 2 pts HTML Editor Question 36 This question is based on the same schema as discussed in Q32. Airline(airlineID, name, country) Passenger(passengerID, name, address) Booking(bookingID, passengerID, airlineID, bookingDate) FlightLeg(bookingID, flightCode, fareType, price, seat) Write an SQL query to give the ids of all passengers who have booked on only one flightCode. 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 22/40 0 words 2 pts HTML Editor Question 37 This question is based on the same schema discussed in Q32. Airline(airlineID, name, country) Passenger(passengerID, name, address) Booking(bookingID, passengerID, airlineID, bookingDate) FlightLeg(bookingID, flightCode, fareType, price, seat) Write an SQL query to find the flightCode(s) that had the most flight reservations. 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 23/40 0 words 2 pts HTML Editor Question 38 This question is based on the same schema discussed in Q32. Airline(airlineID, name, country) Passenger(passengerID, name, address) Booking(bookingID, passengerID, airlineID, bookingDate) FlightLeg(bookingID, flightCode, fareType, price, seat) Write an SQL query to find the average price of each fareType. 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 24/40 0 words 5 ptsQuestion 39 This question is based on the following E-R diagram which describes the information kept on the aircraft based at an airport, including the engineers who are trained to maintain them. 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 25/40 HTML Editor Write SQL CREATE TABLE statements for the Airplane and Model relations from your relational model, as well as any associated relationship relations (PLEASE NOTE: this shouldn't include the Airliner and Cargo Freighter entities). You should show all relevant attributes, types and key constraints for these relations. You should include foreign key integrity constrains, like ON DELETE clauses where suitable, as well as any necessary NOT NULL or UNIQUE constraints. 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 26/40 0 words 12 ptsQuestion 40 Consider a Bank database that provides no concurrency control. The database contains an Account table defined as Account(custId, balance). This table contains these rows before the execution of the following SQL statements: custId balance 3940 11000 4711 8200 5482 12150 Three applications are executing concurrently over this database, two withdrawals (T1 and T2) and the periodic bank-wide interest-adding process (T3). Their operations are interleaved in the following execution schedule: T1 SELECT balance FROM Account WHERE CustId = 3940 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 27/40 HTML Editor T2 SELECT balance FROM Account WHERE CustId = 4711 T3 UPDATE Account SET balance = balance * 1.01 T1 UPDATE Account SET balance = 9000 WHERE CustId = 3940 T2 UPDATE Account SET balance = 8000 WHERE CustId = 4711 What are the balances in all 3 accounts after these operations have completed? [2 marks] Which of the ACID properties are not being maintained in this non- transactional system? [2 marks] Which, if any, of the following anomalies are present in this execution schedule. The possible anomalies are: (i) dirty read, (ii) lost update, (iii) unrepeatable read. [2 marks] Having realised their error, the bank has turned on full SQL transaction support on their database (ISOLATION LEVEL SERIALIZABLE) using strict 2-phase row- level locking, and turned their applications into transactions by wrapping the database within BEGIN and COMMIT statements. The database is reset to the values shown above, and the three applications are re-run, with T1 and T2 again completing their initial SELECTs before T3 attempts its UPDATE, so the start of the execution schedule is the same as before. Write down the revised execution schedule that will have actually occurred as a result of the database enforcing serializable isolation. [3 marks] What would happen if ISOLATION LEVEL had been set to READ COMMITTED instead? Would the previously observed anomaly return? Explain why (or why not) in terms of what locks are held and when they are released. [3 marks] 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 28/40 0 words 14 ptsQuestion 41 The crew members who will be on board a flight are recorded in an un- normalised relation with the following schema: Crew(flightCode,destination,date,tailCode,acName,airline,emp_id,name,title) For example, the row (‘QF141’, ‘Dubai’, ’31-10-2019’, ‘VH-EAB’, ‘City of Canberra’, ‘Qantas’, 65098, ‘Joe Bloggs’, ‘Navigator’) indicates that on 31 October 2019, flight QF141 departed for Dubai on Qantas aircraft VH-EAB (“City of Canberra”) with navigator Joe Bloggs (employee ID 65098) on board. Note that tailCode is the government-issued registration number used to identify an aircraft. You are told that the following functional dependencies apply in this table. flightCode --> destination flightCode, date --> tailCode tailCode --> acName, airline emp_id --> name, title Explain the meaning of the dependency tailCode --> acName, airline. [4 st 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 29/40 HTML Editor marks] The following instance of the table would be illegal according to the functional dependencies given. Identify any one functional dependency which is violated in this instance, and give an example of where it is violated. [4 marks] flightCode destination date tailCode acName airline em NZ700 Auckland 31-10- 2019 VH-EBU City of Broken Hill Air New Zealand 78 CX110 Hong Kong 1-11- 2019 P2-ANH City of Broken Hill Cathay Pacific 78 NZ700 Auckland 31-10- 2019 VH-EBU City of Broken Hill Air New Zealand 78 Give a lossless-join decomposition of the table Crew into a set of BCNF relations. Show that your final relations are in BCNF and no FDs have been lost. [6 marks] 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 30/40 0 words 3 ptsQuestion 42 Nick is curious how Google is protecting his Google account login details against possible hack attacks. As a data professional who has just completed ISYS2120, you are trying to explain to him how the password security is usually implemented at the DBMS level. Nick has the following questions. Please answer each of them in just a few words or a sentence at maximum. Part A) Nick is trying to use the password ‘Apple’ for his account. However, this plain text is not actually what the password system stores in the database. This knowledge is totally new to Nick . Can you please refer to the following picture and explain what processes the letters A and B stand for? [2 marks] 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 31/40 HTML Editor Part B) Can you give an instance of strong hash functions that is currently in use? [1 mark] 12pt Parag 0 words 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 32/40 For the following 5 questions, please read through the scenario description below. Due to a lack of communication between world leaders, there has been a misunderstanding. The 2020 Summer Olympics were double-booked and now both Tokyo and Sydney are going to share responsibility. With full size venues, and half the crowd, this was their unorthodox solution to the problem of social distancing in large crowds. Hence, Alex was assigned to design a database for the Olympic Games. Alex is a recent addition to the team and have found out that not only have they not finished the design, but they have made mistakes. Description: Alex needs to store information about athletes and officials, we need to know their names, gender and country of origin, and each personnel at the games is given an id. Officials do not participate in any sporting events. Each sporting event takes place at a venue, located in or near Sydney. Additionally, athletes and officials stay at accommodation blocks spread across the city. For both venues and accommodation blocks, we need to keep track of the exact address, its GPS position (longitude and latitude), along with a short, memorable unique name. The sports that are played at these events require information such as the name of the sport, whether it was a men’s or women’s competition, the type of score that was given, what category the sport falls under, and whether the sport was team or individual. Task: Your task is to read through the description and identify the mistakes in the following 5 EERD snippets and propose a solution while justifying the need for it. 3 ptsQuestion 43 This question refers to the description provided above. 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 33/40 HTML Editor 12pt Parag 0 words 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 34/40 3 pts HTML Editor Question 44 This question refers to the description provided above 12pt Parag 0 words 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 35/40 3 pts HTML Editor Question 45 This question refers to the description provided above. 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 36/40 0 words 3 pts HTML Editor Question 46 This question refers to the description provided above. 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 37/40 12pt Parag 0 words 3 pts HTML Editor Question 47 This question refers to the description provided above. 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 38/40 12pt Parag 0 words 3 ptsQuestion 48 Bill is interested in exploring Sydney’s data, so he googled ‘tallest tower in Sydney’. Here is the result page: 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 39/40 HTML Editor He is a bit confused about why google returned directly the answer instead of just presenting articles or news including the actual text ‘tallest tower in Sydney’. It seems Google Search functions as a person responding to his question rather than just finding him resources he can refer to. Here are some of his questions. Please answer each of them in just a few words or a sentence at maximum. Part A) What is the underlying mechanism that enables machines to access the certain knowledge and allows users to search for ‘things-not-strings’? [2 marks] Part B) When developing such a data model, what is the common language to use? (one instance will be enough) [1 marks] 12pt Parag 2020/12/9 Quiz: ISYS2120 Semester 2, 2020 Final Exam https://canvas.sydney.edu.au/courses/29248/quizzes/119846/take 40/40 Not saved 0 words Submit Quiz
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