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Consider the following statements regarding database normal forms: 1. Any relation with two attributes is BCNF. 2. Lossless, dependency - preserving decomposition into BCNF is always possible. 3. Lossless, dependency - preserving decomposition into 3NF is always possible. 4. BCNF is stricter than 3NF. Which of the above statements are correct?
Given the following two statements: S1: Every table with two single-valued attributes is in 1NF, 2NF, 3NF and BCNF. S2: AB → C, D → E, E → C is a minimal cover for the set of functional dependencies AB → C, D → E, AB → E, E → C. Which one of the following is CORRECT?
Consider a relational table R that is in 3NF, but not in BCNF, Which one of the following statements is TRUE?
A relation is in Boyce-Codd Normal Form (BCNF) if every determinant is a composite key.
Let A be an m × n matrix and Ban n × m matrix. It is given that determinant ($$I$$m + AB) = determinant ($$I$$n + BA), where $$I$$k is the k × k identity matrix. Using the above property, the determinant of the matrix given below is
\[\left[ {\begin{array}{*{20}{c}} 2&1&1&1 \\ 1&2&1&1 \\ 1&1&2&1 \\ 1&1&1&2 \end{array}} \right
Given the following statements: S1: A foreign key declaration can always be replaced by an equivalent check assertion in SQL. S2: Given the table R (a, b, c) where a and b together form the primary key, the following is a valid table definition. CREATE TABLE S (                 a INTEGER,                 d INTEGER,                 e INTEGER,                 PRIMARY KEY (d)                 FOREIGN KEY (a) references R) Which one of the following statements is CORRECT?
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?
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?
Public key encryption uses multiple keys.ne key is used to encrypt data, while another is used to decrypt data.he key used to encrypt data is called the _______ key, while the key used to decrypt data is called the ________ key.
When they had a meeting seven company executives __ T, U, V, W, X, Y and Z ___ sit at a rectangular table .Three executives sit along one side of the table , and three sit along the other side, each directly opposite one of the other three. The seventh sits at the head of the table . There is no seat at the foot of the table . Ualways sits in one of te two seats farthest from the head of the table. Y and V always sit next to each other .V never sits next to Z . If Z does not sit at the head of the table, W sits there. If W sits directly opposite T, X must sit next to which of the following excutives?