Define three conditions under which it is appropriate to use a surrogate key in place of the primary key of a relation.

Q: When is it important to use an associative entity to express a many-to-many relationship?

A: Associative Entity is used when relationship is to be established in a relation. Like Student and…

Q: Suppose the advisor relationship set were one-to-one. What extra constraints are required on the…

A: GIVEN: Suppose the advisor relationship set was one-to-one. What extra constraints are required on…

Q: By giving an example, define the following terms: A. Coding B. Relation and Relationship

A: Given data:-

Q: Consider the following statements: (1) We can check if a functional dependency holds by examining a…

A: A functional dependency is a relationship between two attributes, typically between the PK and other…

Q: What are the differences between weak and strong entity sets?

A: An entity set is a compilation of similar types of entities. Entities are a crucial idea in…

Q: explanation of three situations in which a relation's secondary key should be set in place of the…

A: The detailed solution is given in the next step.

Q: An ID-dependent Weak Entity typically result in a table with a compound primary key with at least…

A: A weak entity in a relational database is one that can't be uniquely identified by just its…

Q: (6) What are the 2 properties we need to keep in mind while doing decompositions to achieve a…

A: 2 properties are : ✓Lossless Decomposition: If the information is not lost from the relation that is…

Q: Show that if a relation has no attribute that is functionally determined by all the other…

A: Introduction   Show that if a relation has no attribute that is functionally determined by all the…

Q: Analyze the following relation, a) write the types of functional dependencies; c) perform the…

A: For the above table, keys are not defined. Keys can be identified using real time conditions. For…

Q: Describe three circumstances in which a substitute key for a relation's primary key should be…

A: Conditions for recommending a substitute key Three factors indicate that a surrogate key should be…

Q: explanation of three situations in which a relation's secondary key should be set in place of the…

A: Conditions to suggest a surrogate key Three conditions that suggest a surrogate key should be…

Q: Describe three circumstances in which a substitute key for a relation's primary key should be…

A: The question has been answered in step2

Q: Can instances of a relation (sample data)prove the existence of a functional dependency? Why or why…

A: Lets see the solution.

Q: Describe how you would deal with the relation type M:N using a practical example.

A: MANY-TO-MANY (M: N) RELATIONSHIP: Many-to-Many relationship refers to the relationship between two…

Q: Give examples of relations that are: (a) reflexive and symmetric but not transitive (b) reflexive…

A: (a) Reflexive and symmetric but not transitive:   Let's consider a set A = {1, 2, 3}, and define a…

Q: relation's main key and its functional interactions amongst its characteristics are interconnected

A: Please find the answer below :

Q: Question 2. Find a set of FDs for the relation schema R(w, X, y, z) with primary key "wx" under…

A: A set of FDs for the relation schema  R(w, x, y, z) with primary key "wx" under which R is in 2NF…

Q: 2 Consider the following functional dependencies for the given relation. R={A, B, C, D, E, F) AB->CD…

A: Dear Student, The answer to your question is given below -

Q: Under what circumstances can an attribute of a relation be of variable length?

A: An attribute of a relation is the characteristic which is specified in a column. A relation is a…

Q: What's the difference between weak and strong entity sets?

A: What's the difference between weak and strong entity sets?

Q: Assume a relation schema R(a, b, c, d, e, f) with primary key (a, b) and the following full func-…

A: Functional Dependencies:- Functional dependencies are the result of the interrelationship between…

Q: The bus ticketing report shown above displays snippet of the daily transactions. Based on this…

A: The given table is a dataset that stores the route, ticket, customer and travel dates for a bus…

Q: It is the relation among individual entities and values. O principles patterns state relation

A: In  Step 2, I have provided   correct  option-----

Q: Distinguish between the ways in which functional dependencies may be utilized to express the…

A: Identifying the functional dependencies entails the following steps: The functional dependencies may…

Q: explanation of three situations in which a relation's secondary key should be set in place of the…

A: requirements for recommending a surrogate There are three circumstances that indicate a relation's…

Q: Consider a relation (A, B, C, D, E, F, G) with functional dependencies as given below: ABC D ED-F…

A: Consider the following relation with set of functional dependencies: R (A, B, C, D, E, F, G)…

Q: Explain three scenarios in which a surrogate key for a relation's primary key should be generated.

A: Introduction Explain three scenarios in which a surrogate key for a relation's primary key should be…

Q: If aRb ånd bRc together imply cRa. Which of the following options is/are correct? (a) If a relation…

A: The answer is

Q: Give two examples of a relation and their candidate key

A: Candidate key :                          A candidate key is a set of characteristics that uniquely…

Q: HouseSale (houseID, agentID, dateSold, commissionRate, interestRate) Where: dateSold →interestRate…

A: Answer: Given  HouseSale(houseId, agenId, dateSold, commisionRate, InterestRate)…

Q: An explanation of the three circumstances in which the secondary key of a relation should be used…

A: Indicators that point to the existence of a surrogate key There are three circumstances that point…

Q: Explain the relationship between the primary key of a relation and the functional dependencies that…

A: Introduction: A primary key is a database characteristic that uniquely identifies a record.

Q: When is it important to use an associative entity to express a many-to-many relationship?

A: According to the question many to many is used to makes relationship between two or more data or if…

Q: The distinction between a weak and a strong entity collection has to be clarified.

A: In the context of entity collections in a database or data modeling, the distinction between weak…

Q: Please transform the following Entity-Relationship Schema (Diagram) into a Relational Schema. Please…

A: Here PNo and SSno are primary key.  The following are the entities : PROJECT, EMPLOYEE, ENGINEER The…

Q: List three criteria that indicate that a surrogate key should be generated for the main key of a…

A: We have to write three criteria that indicate that a surrogate key should be generated for the main…

Q: 1. Consider the relation schema which records student grades received from courses they have taken…

A: Candidate key: - It is a collection of attributes that recognize rows in a table in a unique way. It…

Q: For relation (R), its attributes and its functional dependencies (F): R(A, B, C, D, E) CD-> B A- D…

A: A relational schema R is considered to be in Boyce–Codd normal form (BCNF) if, for every one of its…

Q: Question 2. Find a set of FDs for the relation schema R(w, X, y, z) with primary key "wx" under…

A: A set of Fd's for the relation schema R(w,x,y,z) with a primary key "WX" under R is in 2nf but not…

Enhanced ER Model

The enhanced ER model is an abbreviation for Enhanced Entity-Relationship (EER) model. As you know, the entity-relationship (ER) model is a pictorial illustration of the relationship between various entities of a domain. In the case of a large amount of data with multiple interrelated entities, the ER diagrams become complex and tough to interpret. For such cases, the need for enhancement in the ER model was observed, and thus, the EER model was designed.