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BU 5010 Database Applications for Managers                                                            

Quiz 1 True / False                                                                                                        Spring 2007

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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.

 F 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.

T 8) It is better to store large amounts of data into an array rather than into a file.

 F 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.

F 12) In random access there is no need for duplication of the file when deleting a record.

T  13) When deleting a record from an array, the physical storage will be deleted.

 F 14) It is necessary to shuffle an array upon deletion to make the insertion faster.

 F 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.

T  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.

T  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.

 F 27) A database schema includes descriptions of the database structure and the constraints that should hold on the database.

T  28) C++ is an example of a DBMS language.

T 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.

T 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:

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.

F  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.

 F 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.

T  39) A binary search is fastest for searching a large unsorted data file.
 

 F 40) Database validation of user input is necessary for fields such as phone number and social security to ensure data integrity.

T  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.

T  44) Access will not allow you to create a one to many relationship due to security.

T  45) Semantic databases are based on the grammar of the expression.

T  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.

T  56)By using a linked list the deleted record will be physically deleted.

T  57) Conceptual data models describe details of how data is stored in the computer.

T  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.