$92.$ITCS$3402\mathrm{.}2317\mathrm{.}319-15$ Midterm Exam Midterm Exam $1$ What does DBMS stand for? $1$ a$.$ None of these b$.$ Database Management System c$.$ Data Base Management Software d$.$ Database Maintenance Software e$.$ Data Backup Management System $2$ Which of the following is an example of a relational database? $2$ a$.$ Neo$4$j b$.$ Cassandra c$.$ None of these d$.$ MySQL e$.$ MongoDB $3$ Which of the following is a method for ensuring data integrity? $3$ a$.$ Data visualization b$.$ Data redundancy c$.$ None of these d$.$ Data isolation e$.$ Integrity constraints $4$ Which of the following is a characteristic of a centralized database? $4$ a$.$ Data stored in various formats b$.$ Requires internet access c$.$ Users access the data even from a remote location d$.$ None of these e$.$ Data spread across multiple locations $5$ What does DDL stand for? $5$ a$.$ Data Description Language b$.$ Data Definition Language c$.$ None of these d$.$ Data Development Language e$.$ Data Deployment Language $6$ Which component of a DBMS is responsible for executing queries? $6$ a$.$ Transaction Manager b$.$ Processor c$.$ Data Dictionary d$.$ Storage Manager Query e$.$ None of these $7$ What is an example of a centralized database system? $7$ a$.$ Oracle Cloud b$.$ SQLite c$.$ None of these d$.$ MySQL e$.$ MongoDB $8$ Which query language is procedural? $8$ a$.$ SQL b$.$ None of these c$.$ DML d$.$ XQuery $9$ What does the term "data redundancy" refer to$?9$ a$.$ Data stored in a single file b$.$ None of these c$.$ Duplicate copies of data d$.$ Storing data in multiple formats e$.$ Loss of data $10$ Which of the following describes a logical schema? $10$ a$.$ Actual data at a moment b$.$ Physical storage of data c$.$ Backup of the database d$.$ None of these $11$ Which operation would you use to combine the results of two queries? $11$ a$.$ None of these b$.$ Join c$.$ Select d$.$ Union e$.$ Project $12$ Which of the following is a property of relations in a relational database? $12$ a$.$ None of these b$.$ Tuples can contain duplicate entries c$.$ Relations are unordered sets of tuples d$.$ The order of tuples is significant e$.$ Each relation can have multiple primary keys $13$ What is the result of a select operation with multiple predicates? $13$ a$.$ Only unique rows are returned b$.$ No rows are returned c$.$ All rows are returned d$.$ None of these e$.$ Only rows that satisfy all predicates are returned $14$ Which of the following is an example of a unary operation in relational algebra? $14$ a$.$ None of these b$.$ Union c$.$ Cartesian Product d$.$ Select e$.$ Join $15$ What is the difference between a relation and a tuple? $15$ a$.$ A relation is a collection of tuples b$.$ None of these c$.$ A relation contains only one tuple d$.$ A tuple is a collection of relations e$.$ There is no difference $16$ What does the 'rename' operation do in relational algebra? $16$ a$.$ Merges two relations b$.$ Changes the values in a relation c$.$ Assigns a new name to an existing relation d$.$ None of these e$.$ Deletes a relation $17$ What is the result of the union operation? $17$ a$.$ A combination of two relations with different attributes b$.$ A new relation without duplicates c$.$ None of these d$.$ A filtered relation based on criteria e$.$ A new relation with duplicates $18$ Which of the following statements about the relational model is true? $18$ a$.$ None of these b$.$ It is based on object$-$oriented principles c$.$ It is complex and difficult to understand d$.$ It abstracts away the details of data storage e$.$ It requires a hierarchical structure $19$ Which of the following is NOT a basic operation in relational algebra? $19$ a$.$ Project b$.$ Select c$.$ Update d$.$ Union e$.$ None of these