DBI202- part 5/7

QN=21 (6829) What is another term for a row in a relational table? a. Attribute b. Tuple c. Field d. Relation

b

QN=13 (6815) Which is the subset of SQL commands used to manipulate Database structures, including tables? a. DDL (Data Definition Language) b. DML (Data Manipulation Language) c. DCL (Data Control Language) d. All of the others

a

QN=15 (6823) "R(A,B,C,D)" is an example of: a. A schema b. A relation c. A relation instance d. A schema instance

a

QN=16 (6813) Which statement is used to remove a column named D from the relation R? a. ALTER TABLE R DROP COLUMN D; b. ALTER TABLE R DROP COLUMN D [DataType]; c. ALTER TABLE R DELETE COLUMN D; d. ALTER TABLE R DELETE COLUMN D [DataType];

a

QN=18 (6817) A ____ is a relation name, together with the attributes of that relation. a. schema b. database c. database instance d. schema instance

a

QN=19 (6822) Which statement is used to add a column named D into the relation R? a. ALTER TABLE R ADD D [DataType]; b. ALTER TABLE R ADD ATTRIBUTE D [DataType]; c. ALTER TABLE R ADD PROPERTY D [DataType];

a

QN=2 (6808) What is a database? a. A database is a collection of information that is organized so that it can easily be accessed, managed, and updated b. A database is a collection of data files c. A database is a collection of records d. A database is a collection of tuples

a

QN=29 (7967) A set of attributes forms a ____ for a relation if we do not allow 2-tuples in a relation instance to have the same values in all that attributes a. Key b. Foreign Key c. Index Key d. Trigger Key

a

QN=11 (6824) A ___ is a notation for describing the structure of the data in a database, along with the constraints on that data a. database management system b. data model c. data operation d. data manipulation

b

QN=20 (6821) Which one of the following is NOT a DML command? a. DELETE b. GRANT c. INSERT d. UPDATE

b

QN=22 (6811) The relational operator that adds all possible pairs of rows from two tables is known as the .... operator. a. union b. product c. join d. selection

b

QN=25 (7969) Consider a relation with schema R(A, B, C, D) and FD's BC -> D, D -> A, A -> B. Which of the following is the key of R? a. BD b. BC c. D d. AB

b

QN=4 (6793) A ______ is a collection of programs that enables user to create and maintain databases. In other words, it is general-purpose software that provides the users with the processes of defining, constructing and manipulating the databases for various applications a. MSSQL b. DBMS c. DBS d. DB2

b

QN=5 (6810) Today, the two important data models are: a. The semi-structured data model (including XML and related standards) and the network data model b. The relational data model (including object-relational extensions) and the semi-structured data model (including XML and related standards) c. The network data model and the flat file data model d. The flat file data model and the semi-structured data model (including XML and related standards)

b

QN=7 (6803) A ____ is a logically coherent collection of data with some inherent meaning, representing some aspect of real world and being designed, built and populated with data for a specific purpose a. Database Instance b. Database c. Schema d. Schema Instance

b

QN=9 (6806) A person who is responsible for the structure or schema of the database is called: a. an end user b. a database administrator c. a database analyst d. all of the others

b

QN=1 (6807) What is a graph database? a. A graph database is a database that uses tree structures with nodes to represent and store information b. A graph database is a database that uses table structures to represent and store information c. A graph database is a database that uses graph structures with nodes, edges and properties to represent and store information d. None of the others

c

QN=10 (6809) A database administrator (DBA) is a person that is also known by the title: a. Database Analyst b. Database Tuner c. Database Coordinator or Database Programmer d. Database Modeller

c

QN=12 (6816) Data Definition language (DDL) is used to ...... a. query database and modify the database b. connect to database and query database c. declare database schemas d. All of the others

c

QN=17 (6831) What is a primary key? a. A primary key is the field(s) in a table that uniquely defines that table in a database b. A primary key is the field(s) in a table that is used to establishes a relationship between two tables c. A primary key is the field(s) in a table that uniquely defines the row in the table d. A primary key is the field(s) in a table that is used to establishes a relationship between two databases

c

QN=23 (7956) Let R(ABCDEFGH) satisfies the following functional dependencies: A -> B, CH -> A, B -> E, BD -> C, EG -> H, DE -> F. Which of the following FDs is also guaranteed to be satisfied by R? a. CGH -> BF b. ACG -> DH c. ADG -> CH d. BCD -> FH

c

QN=27 (7971) Given the relation R(ABCDE) with the following FD's: D -> C, CE ->A, D ->A, and AE ->D Which of the following attribute set is a key? a. ABCDE b. CDE c. ABE d. BD

c

QN=3 (6797) A ____ is a powerful tool for creating and managing large amounts of data efficiently and allowing it to persist over long periods of time, safely a. Excel b. Database c. DBMS d. None of the others

c

QN=30 (7978) The relation R(ABCD) has following FDs: { A -> B ; B -> A ; A -> D ; D -> B } a. R is not in 2NF b. R is not in 3NF c. R is in 3NF d. None of the others

c

QN=14 (6818) Which of the followings is part of data model? a. Structure of the data b. Operations on the data c. Constraints on the data d. All of the others

d

QN=26 (7963) Given the relation schema R(A,B,C) and functional dependencies F = {AB-> C, B->A, C->B}. Which attribute(s) is/are prime? a. only A b. only B c. A and B d. B and C

d

QN=6 (6798) Today, in a modern DBMS, the queries are parsed and optimized by a. all of the others b. execution engine c. buffer manager d. query compiler

d