03/19/07
bu5010
Today's Topic:
we are going to go over the Quiz
BU 5010 Database Applications for Managers
Quiz 1 True / False Spring 2007
Name______________________________________
T 1) A database has operations such as storing, displaying, and searching for records.
T 2) A file should be closed before it is opened again in another operation mode.
T 3) A file can be accessed sequentially as well as randomly.
F 4) The most efficient way to delete from a file is to copy the entire file, excluding deleted data.
T 5) Random access becomes faster if each record has a fixed length with a unique key.
T 6) Binary files store the binary value of a number instead of its ASCII value.
F 7) Modification is more difficult in arrays rather than in a sequential file.
F 8) It is better to store large amounts of data into an array rather than into a file.
T 9) Information in an array will be lost after the program terminates.
T 10) In sequential files, modification requires duplication of the existing file.
T 11) A data file is a file in which data is stored and from which data is retrieved.
T 12) In random access there is no need for duplication of the file when deleting a record.
F 13) When deleting a record from an array, the physical storage will be deleted.
T 14) It is necessary to shuffle an array upon deletion to make the insertion faster.
T 15) If the array is not shuffled after deletion, it is necessary to indicate that the record was deleted.
T 16) A Database is a collection of related data.
F 17) One person having many credit cards is an example of a many-to-many relationship.
F 18) The most important function in a database is delete.
F 19) A database can have at most one table.
T 20) The importance of normalization of a database is to eliminate waste of memory and redundancy of data.
T 21) Simple file encryption can be done by changing ASCII values or by using an associate array.
F 22) A data file is an executable file that performs a database function.
F 23) A database report is used by managers to enter new records to a database.
T 24) A Database Designer’s responsibility is to define the content, the structure, the constraints, and functions or transactions against the database.
F 25) A set of concepts to describe the structure and the constraints of a database is called a data object.
T 26) Three categories of data models are conceptual, physical, and implementation.
T 27) A database schema includes descriptions of the database structure and the constraints that should hold on the database.
F 28) C++ is an example of a DBMS language.
F 29) A primary key is necessary to uniquely identify a record in a table; two records may have the same value in the field designated as primary key.
F 30) Creating relationships between tables increases data redundancy and makes a database less efficient.
T 31) The proper C++ code to open a text file is:ifstream studentFile("students.txt", ios::in);
T 32) In C++, the syntax code if (!fin) can be used instead of if (fin==NULL).
F 33) Unicode consists of 8-16 bits.
T 34) A database consists of many fields.
T 35) A load function will read all records from a file into an array and should be called at the start of a program.
T 36) ifstream fin(“data.txt”,ios::in); if(!fin) cout<<”NO FILE”; will test the file’s existence.
T 37) A file can be opened for both input and output such as fstream fout(“data.dat”, ios::in|ios::out);
T 38) ofstream outfile(“data.txt”, ios::noreplace); prevents an existing file from being overwritten.
F
39) A binary search is fastest for searching a large unsorted data file.
T 40) Database validation of user input is necessary for fields such as phone number and social security to ensure data integrity.
F 41) Sequential search is preferred over hashing because of the speed.
T 42) The C++ system( ) function enables the programmer to use operating system commands.
F 43) In a random access file, seekg( ) is used for putting data and seekp( ) is used for getting data.
F 44) Access will not allow you to create a one to many relationship due to security.
F 45) Semantic databases are based on the grammar of the expression.
F 46) ifstream fin(“data.txt”, ios::in); associates a file for output access.
T 47) You can create CGI web databases using the following programming languages: C/C++ and Perl.
T 48) The three example databases are Access, SQL, and Oracle.
F 49) In order for a C++ database program to read from a textfile it is not necessary to use; #include<fstream>.
F 50) In a C++ database program, it is not required that you include the name of the textfile, in order for the program to locate it and access the data.
F 51) A software package/ system to facilitate the creation and maintenance of a computerized database is known as DBA.
F 53) A set of concepts to describe the structure of a database, and certain constraints that the database should obey is known as Data Model Operations.
T 54)
An entity is an object that is distinguishable from other objects by a
specific set of attributes.
T 55)
Using write( ) function
from <fstream>, one can write an entire structure (record) to a file.
T 56)By
using a linked list the deleted record will be physically deleted.
F 57) Conceptual data models describe details of how data is stored in the computer.
F 58) The Entity Relationship Model consists of entities with no possible relation to each other.
T 59) In the Object Oriented Model, objects consist of data operations on the data.
F 60) The physical implementation of your database files at the lowest level is specified at the conceptual level.