Question

In: Computer Science

For the following schema, provide the following unique/distinct values a) A suitable primary key b) An...

For the following schema, provide the following unique/distinct values

a) A suitable primary key

b) An example of a different candidate key

c) An example of a superkey

Accounts(account_id, account_type_code, customer_id, account_name, date_opened, date_closed, current_balance)

Solutions

Expert Solution

Please find your answers with definition which will help you to understand the concept as well.

a). Ans -> account_id/customer_id

primary key of a set of attribute which can uniquely identify a tuple. Here both account_id or customer_id can uniquelly identify the rows uniquily as these vlues are unique for rach customer. Prinamy key can be combination of account_id_customer_id as well. There can be more than one candidate key in relation out of which one can be chosen as the primary key.

b). account_id/customer_id but not account_id_customer_id as the definition of Cndidate key states that The minimal set of attribute which can uniquely identify a tuple is known as candidate key. so account_id/customer_id is minimal but not account_id_customer_id as it's a combination of two PK's.

c). (account_id, account_type_code), (account_id, customer_id),(account_id, customer_id), (account_id, date_opened)..etc

(customer_id, account_id), (customer_id, date_opened),  (customer_id, date_closed),  (customer_id, current_balance) .. etc

The set of attributes which can uniquely identify a tuple is known as Super Key.


Related Solutions

1a) i) Explain the candidate key, primary key and foreign key with suitable examples [6] ii)...
1a) i) Explain the candidate key, primary key and foreign key with suitable examples [6] ii) Draw a suitable ER diagram to show the “IS-A” relationship between subtype and supertype [5] iii) Briefly explain the recursive relationship with a suitable example. [2]
Assuming Database is not providing Referential Integrity Constraints support i-e Primary key, foreign key and Unique...
Assuming Database is not providing Referential Integrity Constraints support i-e Primary key, foreign key and Unique key, your task is to design a database engine with your own built in Referential integrity rules implementation and you need that only one database connection is maintained which an application should access. Recommend proper design pattern used for the stated problem. Give reasons for selecting that pattern, create complete class diagram for the solution. The class diagram should also show the methods of...
1. Use SQL to create a polyinstantiated table including a primary key and a unique constraint...
1. Use SQL to create a polyinstantiated table including a primary key and a unique constraint 2.Use SQL to insert multiple records for each security classification with the same ID. You must have 4 classifications. 3.Use SQL to create 4 schemas, one for each security classification 4.Use SQL to create a view in each schema that restricts the records to those belonging to a particular security classification and restricts the columns to only those columns that have relevant data. 5.Select...
Consider the following relational schema about a University (the primary keys are underlined and foreign keys...
Consider the following relational schema about a University (the primary keys are underlined and foreign keys are italic) STUDENT(StudentID, name, major, year, age) CLASS(ClassName, meetsAt, room, LecturerID) ENROLLED(StudentID, ClassName, mark) LECTURER(LecturerID, name, DepartmentID) DEPARTMENT(DepartmentID, name) Write the SQL statements for the following query: B1. Find the age of the oldest student. B2. Find the ID’s of lecturers whose name begins with “K” \ B3. Find the age of the youngest student who is enrolled in Mechatronics. B4. Find the age...
Provide the following parameter values for each of the IPv4 network classes, A, B, and C,...
Provide the following parameter values for each of the IPv4 network classes, A, B, and C, respectively. Ignore any reserved addresses. a. Class id b. Number of bits in network portion of address, including the class id c. Number of bits in host portion of address d. Number of distinct networks allowed e. Number of distinct hosts allowed per network
Identify every possible primary key, candidate key, and foreign key for the following relations. Separate each...
Identify every possible primary key, candidate key, and foreign key for the following relations. Separate each key using a semicolon to avoid confusion. Assumptions: MIScompany has branches located in several states within the United States. A customer can be an individual or organization. driverId is the driving license number, ssno is the social security number and upc is the universal product code. Any equipment is rented and returned at the same branch. A customer can be a manufacturer and vice...
Which of the following best describes the primary key? Select one: a. It's the encryption key...
Which of the following best describes the primary key? Select one: a. It's the encryption key that gets exchanged first with another party. b. It's the password that needs to be entered to open the database. c. It's the first item that is entered into the database on a screen. d. It's a field that uniquely identifies the record.
The following language over Σ = {1, #} contains #-separated lists of distinct unary values: A...
The following language over Σ = {1, #} contains #-separated lists of distinct unary values: A = {x1#x2# . . . #xk | k ≥ 0, xi = 1∗ for all i = 1 . . . k, xi 6= xj for all i 6= j} Use the pumping lemma to show A is not regular. In other words, give a string s ∈ A and argue that no matter how you partition s = xyz with |y| > 0,...
Consider the following schema and functional dependencies: SHIPPING (ShipName, ShipType, VoyageID, Cargo, Port, ArrivalDate) Key: ShipName,...
Consider the following schema and functional dependencies: SHIPPING (ShipName, ShipType, VoyageID, Cargo, Port, ArrivalDate) Key: ShipName, ArrivalDate FD1: ShipName > ShipType FD2: VoyageID > ShipName, Cargo FD3: ShipName, ArrivalDate > VoyageId, Port 1.Please list the final set of 3NF schema including all its keys. 2.Do any of the finalized 3NF schema have determinates that are not candidate keys? If yes, explain - which schema(s)? Why?  
Determine a suitable process model for the following projects. Also, you are required to provide a...
Determine a suitable process model for the following projects. Also, you are required to provide a short justification along with the necessary assumptions Choose any THREE projects. a) The control system for an Unmanned aerial vehicle (UAV), where all the stakeholders’ requirements are clear and well defined. b) An online medical store where users are not determined about their requirements. However, cost, errors avoidance and implementation have a higher priority over the functionality, which can be added in later versions....
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT