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Higher Study | DBMS | Integrity Constraints and Normal Form

A relation Empdtl is defined with attributes empcode (unique), name, street, city, state and pincode. For any pincode, there is only one city and state. Also, for any given street, city and state, there is just one pincode. In normalization terms, Empdtl is a relation in:
For a database relation R(a, b, c, d) where the domains of a, b, c and d include only atomic values, only the following functional dependencies and those that can be inferred from them hold a → c b → d The relation is in
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?
Relation R has eight attributes ABCDEFGH. Fields of R contain only atomic values. F = {CH → G, A → BC, B → CFH, E → A, F → EG} is a set of functional dependencies (FDs) so that F+ is exactly the set of FDs that hold for R. How many candidate keys does the relation R have?
Consider the relation schema: Singer(singerName, songName). What is the highest normal form satisfied by the "Singer" relation schema?
Which of the following normal form(s) is/are based on the functional dependencies among the attributes of a relation? A. 1NF B. 2NF C. 3NF D. 4 NF
Boyce Codd Normal Form is slightly stronger version of which of the form of database normalisation?
We have a database table with relational schema R(XYZPQ): X Y Z P Q A1 B1 C1 D1 E1 A2 B2 C1 D2 E1 A3 B2 C2 D1 E2 A4 B3 C1 D3 E3 A5 B2 C2 D4 E2   Which of the following statements is true?
Which of the following statements is/are FALSE? (i) By definition a relation schema is in first normal form. (ii) A relation schema which is in third normal form is definitely in BCNF.
Let R is a relation schema and X, Y ⊆ R. "If Y ⊆ X, then X → Y" represents which of the following inference rules?
Let R(A, B, C, D) be a relation schema and F = {A → BC, AB → D, B → C} be the set of functional dependencies defined over R. Which of the following represents the closure of the attribute set {B}?
Match the following with respect to RDBMS: A. Entity integrity 1. enforces some specific business rule that do not fall into entity or domain B. Domain integrity 2. Rows can’t be deleted which are used by other records C. Referential integrity 3. enforces valid entries for a column D. User defined integrity 4. No duplicate rows in a table
Given an instance of the relation R(ABCD). A B C D a1 b1 c1 d1 a1 b2 c2 d2 a2 b2 c2 d3 a3 b3 c4 d3   Which of the following functional dependencies hold?
 Which of the following statements best describes the main reasons for normalizing relational database? I. To achieve physical data independence.  II. To remove data anomalies (insertion, update, deletion, anomalies).  III.  To save space on Disk. 
Given a relation schema R(ABCDEFGH) in first normal form. For the set of dependencies F={ A → B, A → C, CG → H, B → H, G → F}, which dependency is logically implied?
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