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Consider a schema R(A, B, C, D) and functional dependencies A -> B and C -> D. Then the decomposition of R into R1 (A, B) and R2(C, D) is

Consider a schema R(A, B, C, D) and functional dependencies A -> B and C -> D. Then the decomposition of R into R1 (A, B) and R2(C, D) is Correct Answer not dependency preserving and not lossless join

While decomposing a relational table we must verify the following properties: i) Dependency Preserving Property ii) Lossless-Join Property.

Related Questions

Consider the following four relational schemas. For each schema, all non-trivial functional dependencies are listed. The underlined attributes are the respective primary keys. Schema I: Field ‘courses’ is a set-valued attribute containing the set of courses a student has registered for. Non-trivial functional dependency: rollno → courses Schema II: Non-trivial functional dependencies: rollno, courseid → email email → rollno Schema III: Non-trivial functional dependencies: rollno, courseid → marks, grade marks → grade Schema IV: Non-trivial functional dependencies: rollno, courseid → credit courseid → credit Which one of the relational schemas above is in 3NF but not in BCNF?
The following functional dependencies hold true for the relational schema R{V, W, X, Y, Z}: V → W VW → X Y → VX Y → Z Which of the following is irreducible equivalent for this set of functional dependencies?
Let the set of functional dependencies F = {QR → S, R → P, S → Q} hold on a relation schema X = (PQRS). X is not in BCNF. Suppose X is decomposed into two schemas Y and Z, where Y = (PR) and Z = (QRS). Consider the two statements given below. I. Both Y and Z are in BCNF II. Decomposition of X into Y and Z is dependency preserving and lossless Which of the above statements is/are correct?
Consider the relation R(P, Q, S, T, X, Y, Z, W) with the following functional dependencies. PQ → X; P → YX; Q → Y; Y → ZW Consider the decomposition of the relation R into the constituent relations according to the following two decomposition schemes. D1 : R = [(P, Q, S, T); (P, T, X); (Q, Y); (Y, Z, W)] D2 : R = [(P, Q, S); (T, X); (Q, Y); (Y, Z, W)] Which one of the following options is correct?
Consider the schema R (A, B, C, D) and the functional dependencies  A → B and C → D. If the decomposition is made as R1 (A, B) and R2 (C, D), then which of the following is TRUE ?
Relation R with an associated set of functional dependencies, F, is decomposed into BCNF. The redundancy (arising out of functional dependencies) in the resulting set of relations is
A database of research articles in a journal uses the following schema. (VOLUME, NUMBER, STARTPAGE, ENDPAGE, TITLE, YEAR, PRICE) The primary key is (VOLUME, NUMBER, STARTPAGE, ENDPAGE) and the following functional dependencies exist in the schema. (VOLUME, NUMBER, STARTPAGE, ENDPAGE) → TITLE (VOLUME, NUMBER) → YEAR (VOLUME, NUMBER, STARTPAGE, ENDPAGE) → PRICE The database is redesigned to use the following schemas. (VOLUME, NUMBER, STARTPAGE, ENDPAGE, TITLE, PRICE) (VOLUME, NUMBER, YEAR) Which is the weakest normal form that the new database satisfies, but the old one does not?  
The _______ is a set of all functional and multi values dependencies implied by a set of functional dependencies
A _________ Fc for F is a set of dependencies such that F logically implies all dependencies in Fc, and Fc logically implies all dependencies in F.
The algorithm that takes a set of dependencies and adds one schema at a time, instead of decomposing the initial schema repeatedly is