Let a prime attribute be one that appears in at least one candidate key. Let α and β be sets of attributes such that α → β holds, but β → α does not hold. Let A be an attribute that is not in α, is not in β, and for which β → A holds. We say that A is transitively dependent on α. We can restate the definition of 3NF as follows: A relation schema R is in 3NF with respect to a set F of functional dependencies if there are no nonprime attributes A in R for which A is transitively dependent on a key for R. Show that this new definition is equivalent to the original one.

Q: Consider a relation with schema R(A,B,C,D,E,G) and functional dependencies (FDs) C→D; B→A; D→E; E→G…

A: Answer is given below .

Q: 3. Disprove the following rule: {B > CD, AB → E, E → C} |= {AE → CD} To disprove a rule, construct a…

A:

Q: Consider the relation R = {A, B, C, D, E, F, G, H, I,J} and the set of functional dependencies F = {…

A: f ={     AB → C,      A → D,      B → F,  F → GH,  D → IJ   } To find the key check the RHS of the…

Q: Consider the following functional dependencies for a relation R(A, B, C, D) A -> (B, C, D), (A, D)…

A: Given relation with functional dependencies is: R(A, B, C, D) A -> (B, C, D), (A, D) -> (B, C)…

Q: Now start with these functional dependencies: АВ > Е C → D F → GH FG → GH В > FG Find a minimal…

A: A) AB ->E, C->D, F->GH, FG->GH, B->FG Here in FD FG->H, we can delete G from RHs…

Q: Consider a relation T on Z where T = (1,1)}. Is T reflexive? Is T symmetric? Is T transitive?…

A: Given a relation T on Z T={(1,1)}   T is not reflexive because Z is integer and has many element so…

Q: Consider the relation R(A, B, C, D, E), and the decomposition of R into R1(ABC) and R2(ADE). (a)…

A:

Q: Consider a relation R={A,B,C,D,E,F,G,H,I} with the set of functional dependencies and determine,…

A: Now we must determine the above definition whether for each FD. Each value is super key or not on…

Q: From the given set of functional dependencies,determine that there can be more than one canonical…

A: Functional dependency is a relationship that is shown between two or more attributes of a table.…

Q: Let FD ={G → A, A → BC, C → FG, E → HG} be a set of functional dependencies. Calculate the…

A:

Q: Consider a relation schema R = {A, B, C, D, E, F, G} with the following set of functional…

A: A relational schema R with the set of functional dependencies

Q: Consider a relation schema R = {A, B, C, D, E} and its functional dependency set F = {A → BC,CD →…

A: The given relation is lossless-join decomposition and not dependency preserving. Hence, correct…

Q: Consider a relation (p, q, r, s, t, u, v) with functional dependencies as given below: p>q r>s,t…

A: Defined candidate key for the given relational schema

Q: Consider the relation R = {F, T, D, N, S} and the set of functional dependencies K = {F¬D, {D, T}…

A:

Q: Let's suppose, a relation R=(A, B, C, D, E. H) with a set of functional dependencies F: (AE->BC, B…

A: Functional dependency is a DBMS concept . In this attributes of relations  are dependent on each…

Q: Consider a relation schema R = (X, Y, Z) on which the following functional dependencies hold: {XY →…

A: Here in this question we have given a relation schema R = (X, Y, Z) on which the following…

Q: For a given relationship set, R = {A, B, C, D, E, F} and FD : A->B, C->D, E->F . Calculate F+ of A,…

A: Closure of an Attribute: A set of attributes that can be functionally derived from an attribute is…

Q: Question 5 Let set A = {1, 2, 3} and S is a relation on set A, where S= {(1, 1), (1, 2), (1, 3), (2,…

A: Relation S is said to be transitive as for a,b,c in A, if (a,b) is in R and (b,c) is in S, then…

Q: 3. Consider a relation R from X={1,2,3,4} to Y={a,b,c,d). R= {(1,b), (2,c), (2,d), (3,c), (4,a) }…

A: In this question we have to consider the relation R from  X = {1, 2, 3, 4} to Y={a, b, c, d} R =…

Q: 2. Let A = {0, 1}. Determine all relations on A.

A: Answer: All relations of A are listed below.  R1={} R2={(0,0),(0,1),(1,0),(1,1)} R3={(0,0)}…

Q: Q2: Given relation R with attributes (A, B, C, D, E, F). Give all the keys of R if the functional…

A: Given relation R(A, B, C, D, E, F)   Functional Dependencies: AB → C,  CD → E,  E → F   A, B, D do…

Q: relation R (W,I,S,D,O,M) with the following eight functional dependencies: F: {WI → S; D → OM; S →…

A: Note: Answering the first three subparts as per the guidelines. Given : F: {WI → S; D → OM; S → W;…

Q: QUESTION 6 Consider the following functional dependencies for a relation R(A, B, C, D) A -> (B, C,…

A: A super key whose any proper subset is not super key is called candidate key.   closure table : (A)+…

Q: Consider the relation scheme R (A, B, C, D, E) and the set of functional dependencies F = { A –→ BC;…

A: Closure (A) =(A, B, C, D, E)  Closure(CD) =(C, D, E, A, B)  Closure (B) =(B, D)  Closure (E) =(E, A,…

Q: Given a relation R(W, X, Y, Z) and Functional Dependency set PQ = { WX -> YZ, X->Y }, determine…

A: According to the information given:- We have to define the given relation R(w,x,y,z) and functional…

Q: The multiple choice answers are: - One and only one - one or many - zero or one - zero or many.

A: The cardinalities are given below with explanation

Q: Let A1, A2, and A3 be attributes in a relation R. If both of these functional dependencies hold: A1…

A:

Q: All parts of this question use the relation R = (ABCDEG) with the set of functional dependencies F…

A: 1) The given relation is : R = (ABCDEG) The given set of functional dependencies F is : A→BC AD→G…

Q: Assume that R is a relation on {1, 2, 3, 4} defined as follows: a R b if and only if a + b is an odd…

A: As the relation is possible when the sum of values in a pair is a odd value.

Q: Consider the relation R with the following functional dependencies: R(P,Q,R, D,E,F) FD = {P →Q, QR →…

A: The set of attributes PEF, QFR is the candidate keys for the given relation R. Therefore, the right…

Q: Let X= {4,5,6}.If we define a relation R on X by (x,y) ER if x<y, x,yEX, then R=

A: Solution is given in next step:

Q: Let R be the relation on the set A = {1, 2, 3} such that R is {(1,1) ,(1,2), (2,2),(2,3), (3,1),…

A: Let's discuss about Reflexive and symmetric relation. Reflexive Relation A relation R on a set A is…

Intermediate SQL Concepts

A query is a request for data or information from one or more database tables. This information could be presented in the form of pictorials, graphs, or complicated findings which helps in easy interpretation. Structured Query Language (SQL) is the most widely used programming language for retrieving and organizing data from relational databases. Collection of tables with rows and columns is referred to as a database. SQL is the language of databases. It makes it easier to extract specific data from databases, which can then be used for analysis.