Journal

Dr. Alireza Ebrahimi

The captain cannot be late.

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A large-scale web search engine is a complex system and much remains to be done. Our immediate goals are to improve search efficiency and to scale to approximately 100 million web pages. Some simple improvements to efficiency include query caching, smart disk allocation, and subindices. Another area which requires much research is updates. We must have smart algorithms to decide what old web pages should be recrawled and what new ones should be crawled. Work toward this goal has been done in [Cho 98]. One promising area of research is using proxy caches to build search databases, since they are demand driven. We are planning to add simple features supported by commercial search engines like boolean operators, negation, and stemming. However, other features are just starting to be explored such as relevance feedback and clustering (Google currently supports a simple hostname based clustering). We also plan to support user context (like the user's location), and result summarization. We are also working to extend the use of link structure and link text. Simple experiments indicate PageRank can be personalized by increasing the weight of a user's home page or bookmarks. As for link text, we are experimenting with using text surrounding links in addition to the link text itself. A Web search engine is a very rich environment for research ideas. We have far too many to list here so we do not expect this Future Work section to become much shorter in the near future.

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Christian contributed this from : From Wikipedia, the free encyclopedia

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Demo this java script program to receive extra points

import java.io.*;
public class Database {
private staticfinal int MAX = 100;
private Cin cin =new Cin();
private Stringname[] = new String[MAX];
private doublehourlyrate[] = new double[MAX];
private doublehoursworked[] = new double[MAX];
private doublegrosspay[] = new double[MAX];
private StringsearchName;
private StringfileName;
private int n =0;
public void load()throws IOException{
try{ Reader fi = new BufferedReader(
newInputStreamReader(
new FileInputStream("employee.dat")));
StreamTokenizer fin = new StreamTokenizer(fi);
int tokenType;
tokenType= fin.nextToken();
while((tokenType != StreamTokenizer.TT_EOF)){
name[n] = fin.sval;
fin.nextToken();
hourlyrate[n] = fin.nval;
fin.nextToken();
hoursworked[n] = fin.nval;
grosspay[n] = hoursworked[n] * hourlyrate[n];
tokenType = fin.nextToken();
n++;}//WHILE
}//TRY
catch(IOException ex){ System.out.println(ex); }//CATCH
}//LOAD
public voidinsert(){
System.out.print("Enter the employee name: ");
name[n] =cin.readString();
System.out.print("What is employee hourly rate? ");
hourlyrate[n]= cin.readDouble();
System.out.print("How many hours did theemployee work? ");
hoursworked[n]= cin.readDouble();
grosspay[n] =hoursworked[n] * hourlyrate[n];
n++;}//INSERT
public voiddisplay(){
for ( int i =0; i<n; i++ ){
if(name[i]!=""){
System.out.println( name[i] + " " + grosspay[i] );}//IF
}//FOR
}//DISPLAY


public boolean search(){
System.out.print("Enter the search name: ");
String searchName = cin.readString();
for(int i = 0; i < n; i++){
if ( searchName.equalsIgnoreCase(name[i])){
System.out.println("Found: "+name[i]);
System.out.println("Grosspay: "+grosspay[i]);
return true; }//IF
}//FOR
System.out.println("Name not found");
return true;
}//SEARCH
public boolean modify(){
System.out.print("Enter the search name: ");
String searchName = cin.readString();
for(int i = 0; i < n; i++){
if ( searchName.equalsIgnoreCase(name[i])){
System.out.print("What is employee hourly rate? ");
hourlyrate[i] = cin.readDouble();
System.out.print("How many hours did the employee work?");
hoursworked[i] = cin.readDouble();
grosspay[i] = hoursworked[i] * hourlyrate[i];
return true; }//IF
}//FOR
System.out.println("Name not found");
return false;
}//MODIFY
public boolean remove(){
System.out.print("Enter the search name: ");
String searchName = cin.readString();
for(int i = 0; i < n; i++){
if ( searchName.equalsIgnoreCase(name[i])){
name[i] = "";
return true; }//IF
}//FOR
System.out.println("Name not found");
return false;
}//REMOVE
public void quit() throws IOException{
this.store();
System.out.println("Thank you");
System.exit(0);
}//QUIT
public void store() throws IOException{
try{
FileOutputStream out = new FileOutputStream("employee.dat");
PrintStream ps = new PrintStream(out);
for(int i = 0; i < n; i++){
if ( name[i] != "" )
ps.println( name[i] + "\t" + hourlyrate[i] +
"\t" + hoursworked[i] );
}//FOR
out.close(); }//TRY
catch( IOException ex ){
System.out.println(ex); }//CATCH
}//STORE


public static void main( String args[] ) throws IOException{
Database db = new Database();
Cin read = new Cin();
db.load();
int choice = 0;
do{System.out.println("\t1-Insert");
System.out.println("\t2-Display");
System.out.println("\t3-Search");
System.out.println("\t4-Modify");
System.out.println("\t5-Remove");
System.out.println("\t6-Quit");
choice = read.readInt();
if( choice == 1 ) db.insert();
else if( choice == 2 ) db.display();
else if( choice == 3 ) db.search();
else if( choice == 4 ) db.modify();
else if ( choice == 5 ) db.remove();
else if ( choice == 6 ) db.quit();
else System.out.println("Enter correct number");
} while(true);
}//MAIN
}//DATABASE

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Journal Monday April 16th, 2008

Subtopic of today:

What is Command Line Argument Management: Argument c(argc), Argument v(argv)

How do you make Select Command from C++ with the Command Line Argument.

Te Final questions: 20pts each.

1- Your task is to encrypt all sensitive data (security, privacy) in your database and get rid of the original data (delete files or fields ). -The key for running the encryption is "the quick brown fox jumps over the lazy dog". program is not case sensitive, deal with special characters and numbers in your own creative way. To test your program decrypt the data to get to original database. The test data input is HELLO and the encrypted output you should get is PTFFB. Hint, you may want to use an other key for numbers and special characters.

"the quick brown fox jumps over the lazy dog"
 abcdefghijklmnopqrstuvwxyz, skip letters that are repeated such as "o", "e"

2- You are to design a database from scratch using any file access and memory access mode (sequential, random, array, object, etc.) Be unique and creative. You may want to use C++ or any programming language you are familiar with. show your data file and queries.

3- you are to design a database using access, DB2, Oracle, etc. Use your own SQL query to access the similar data as in question two.

4-How does the program on page 703 work if you can explain thoroughly.  20pts.

5-Why should a manager be acquainted with database and its related issues. what is the cost and benefits? (Pros/Cons) The format will be according to the management article on www.ebrahimi.com

ex. The research part of the essay is to get job description/requirements for manager positions.

ex. from essay format:
Why Managers Should Become Better Acquainted
With Programming Issues, Web Source Code, and
Technology?
Alireza Ebrahimi, State University of New York,
College at Old Westbury, USA
Abstract
There has been a controversial debate over how well managers need to acquainted with the area of information technology, especially about what managers need to know of programming and understanding of web source code. Information is an indispensable key to business success

Journal Monday

 March 31st, 2008

Go to page 701 and Type and Run the program.

<HTML>

<BODY BGCOLOR=ffdeaa>

<CENTER><BR><B>Employee Database</B></CENTER><BR>

<HR WIDTH=65%>

<CENTER>Please select from the following choices:<BR><BR>

<FORM ACTION="insertrecord.html">

<INPUT TYPE="submit" VALUE="1. Insert a Record "></FORM>

<FORM ACTION="cgi-bin/displayall.cgi">

<INPUT TYPE="submit" VALUE="2. Display all Records "></FORM>

<FORM ACTION="search.html">

<INPUT TYPE="submit" VALUE="3. Search Database "></FORM>

<FORM ACTION="cgi-bin/update.cgi">

<INPUT TYPE="submit" VALUE="4. Update Record "></FORM>

<FORM ACTION="cgi-bin/delete.cgi">

<INPUT TYPE="submit" VALUE="5. Delete a Record "></FORM>

</CENTER></BODY>

</HTML>

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<HTML>
<BODY BOCOLOR=FFDEAA>
<CENTER><BR><B>Employee Database</B></CENTER><BR>
<HR WIDTH=65%>
<CENTER>Please select from the following choices:<BR><BR>
<FORM ACTION=="insertrecord.html">
<INPUT TYPE="submit"VALUE="1. Insert a record "></FORM>
</CENTER></BODY>
</HTML>

Journal Wednesday

 March 26th, 2008

Q1- Your task is to encrypt all sensitive data (security, privacy) in your database and get rid of the original data (delete files or fields ). -The key for running the encryption is "the quick brown fox jumps over the lazy dog". program is not case sensitive, deal with special characters and numbers in your own creative way. To test your program decrypt the data to get to original database. The test data input is HELLO and the encrypted output you should get is PTFFB. Hint, you may want to use an other key for numbers and special characters.(40 points)

"the quick brown fox jumps over the lazy dog"
 abcdefghijklmnopqrstuvwxyz, skip letters that are repeated such as "o", "e"

Q2- You are to design a database from scratch using any file access and memory access mode (sequential, random, array, object, etc.) Be unique and creative. You may want to use C++ or any programming language you are familiar with. show your data file and queries.(30 points)

Q3- you are to design a database using access, DB2, Oracle, etc. Use your own SQL query to access the similar data as in question two. (30 points)

ENCRYPTION EXAMPLE
Following is a sample PL/SQL program to encrypt data. Segments of the code are numbered and contain
narrative text explaining portions of the code.
DECLARE
input_string VARCHAR2(16) := ’tigertigertigert’;
key_string VARCHAR2(8) := ’scottsco’;
encrypted_string VARCHAR2(2048);
decrypted_string VARCHAR2(2048);
error_in_input_buffer_length EXCEPTION;
PRAGMA EXCEPTION_INIT(error_in_input_buffer_length, -28232);
INPUT_BUFFER_LENGTH_ERR_MSG VARCHAR2(100) :=
’*** DES INPUT BUFFER NOT A MULTIPLE OF 8 BYTES ***’;
1. Test string data encryption and decryption-- The interface
for encrypting raw data is similar.
BEGIN           This is the beginning of the program
dbms_output.put_line(’> ========= BEGIN TEST =========’);
dbms_output.put_line(’> Input String :
’ ||
input_string);
BEGIN
dbms_obfuscation_toolkit. input_string => input_string,
key_string => key_string, encrypted_string =>
encrypted_string );
dbms_output.put_line(’> encrypted string : ’
||
encrypted_string);
dbms_obfuscation_toolkit.DESDecrypt(input_string =>
encrypted_string,
key => raw_key, decrypted_string =>
decrypted_string);
dbms_output.put_line(’> Decrypted output : ’
||
decrypted_string);
dbms_output.put_line(’> ’);
if input_string = here is an "if" statement
decrypted_string THEN
dbms_output.put_line(’> DES Encryption and Decryption
successful’);
END if;
EXCEPTION
WHEN error_in_input_buffer_length THEN
dbms_output.put_line(’> ’ ||
INPUT_BUFFER_LENGTH_ERR_MSG);
END;
 

insert into <table> [(<column i, . . . , column j>)] <query>

Journal Monday

 March 24, 2008

Q1- Your task is to encrypt all sensitive data (security, privacy) in your database and get rid of the original data (delete files or fields ). -The key for running the encryption is "the quick brown fox jumps over the lazy dog". program is not case sensitive, deal with special characters and numbers in your own creative way. To test your program decrypt the data to get to original database. The test data input is HELLO and the encrypted output you should get is PTFFB. Hint, you may want to use an other key for numbers and special characters.(40 points)

"the quick brown fox jumps over the lazy dog"
 abcdefghijklmnopqrstuvwxyz, skip letters that are repeated such as "o", "e"

Q2- You are to design a database from scratch using any file access and memory access mode (sequential, random, array, object, etc.) Be unique and creative. You may want to use C++ or any programming language you are familiar with. show your data file and queries.(30 points)

Q3- you are to design a database using access, DB2, Oracle, etc. Use your own SQL query to access the similar data as in question two. (30 points)

Journal Wednesday February 27, 2008

THIS WORK BELOW IS DUE ON MONDAY FIRST 1/2 OF THE CLASS

- We will retake the test to the online and we will log on to:   https://oldwestbury.sln.suny.edu/frames.aspx and log in.

1 -On page 297 run the program as is FIRST

2 -Change this so it becomes a Membership Database such as username and password.

3 - Encrypt the password before saving it to the file.

Today we will show you a program in Dev C++ from page 297.

Each student should reproduce the program on their own workstation.   The program above does not have all of the functions declared and will not compile.

Below is version 2 of the program with all of the functions coded.

#include<iostream>
using namespace std;
char rfappend(){
cout<<"Append Under Construction "<<endl;
return 0;
}
char rfdisplay(){
cout<<"Append Under Construction "<<endl;
return 0;
}
char rfsearch(){
cout<<"Append Under Construction "<<endl;
return 0;
}
char rfmodify(){
cout<<"Append Under Construction "<<endl;
return 0;
}
char rfdelete(){
cout<<"Append Under Construction "<<endl;
return 0;
}
main(){char option;
cout<<"SELECT ONE OF THE FOLLOWING "<<endl;
cout<<"\t TYPE 1 TO INSERT "<<endl;
cout<<"\t TYPE 2 TO DISPLAY "<<endl;
cout<<"\t TYPE 3 TO SEARCH "<<endl;
cout<<"\t TYPE 4 TO MODIFY"<<endl;
cout<<"\t TYPE 5 TO DELETE "<<endl;
cout<<"\t TYPE # TO QUIT "<<endl<<endl;
cin>>option;
switch(option){
case '1': rfappend();
break;
case '2': rfdisplay();
break;
case '3': rfsearch();
break;
case '4': rfmodify();
break;
case '5': rfdelete();
break;
case '#': cout<<"BYE "<<endl;
exit(1);
break;}//SWITCH
system ("Pause");
return 0;
}
 

Testing our program...

Testing is VERY important.   Many databases and programs are not tested enough.

Make your messages friendly and clear.

#include<iostream>
using namespace std;
char rfappend(){
cout<<"Append Under Construction "<<endl;
return 0;
}
char rfdisplay(){
cout<<"Display Under Construction "<<endl;
return 0;
}
char rfsearch(){
cout<<"Search Under Construction "<<endl;
return 0;
}
char rfmodify(){
cout<<"Modify Under Construction "<<endl;
return 0;
}
char rfdelete(){
cout<<"Delete Under Construction "<<endl;
return 0;
}
main(){char option;
while(1){
cout<<"SELECT ONE OF THE FOLLOWING "<<endl;
cout<<"\t TYPE 1 TO INSERT "<<endl;
cout<<"\t TYPE 2 TO DISPLAY "<<endl;
cout<<"\t TYPE 3 TO SEARCH "<<endl;
cout<<"\t TYPE 4 TO MODIFY"<<endl;
cout<<"\t TYPE 5 TO DELETE "<<endl;
cout<<"\t TYPE # TO QUIT "<<endl<<endl;
cin>>option;
switch(option){
case '1': rfappend();
break;
case '2': rfdisplay();
break;
case '3': rfsearch();
break;
case '4': rfmodify();
break;
case '5': rfdelete();
break;
case '#': cout<<"BYE "<<endl;
exit(1);
break ;
default: cout<<"Enter 1 to 5"<<endl;
}//SWITCH
}//WHILE
system ("Pause");
return 0;
}

The code with the append function

#include<iostream>
#include<fstream>
#include<iomanip>
using namespace std;
char rfappend(char personname[], char phone[]){
ofstream fout("directory.in",ios::app);
cout<<"ENTER PERSON NAME ";
cin>>personname;
cout<<"ENTER THE PHONE NUMBER ";
cin>>phone;
fout<<personname<<setw(20)<<phone<<endl;
fout.close();

return 0;
}
char rfdisplay(char personname[], char phone[]){
ifstream fin ("directory.in");
while (fin>>personname>>phone){
cout<<"PERSON NAME IS "<<personname<<endl<<endl;
cout<<"PHONE IS "<<phone<<endl<<endl; }//WHILE
fin.close();
return 0; }
char rfsearch(){
cout<<"Search Under Construction "<<endl;
return 0;
}
char rfmodify(){
cout<<"Modify Under Construction "<<endl;
return 0;
}
char rfdelete(){
cout<<"Delete Under Construction "<<endl;
return 0;
}
main()
{char personname[100], phone[10],option;
while(1){
cout<<"SELECT ONE OF THE FOLLOWING "<<endl;
cout<<"\t TYPE 1 TO INSERT "<<endl;
cout<<"\t TYPE 2 TO DISPLAY "<<endl;
cout<<"\t TYPE 3 TO SEARCH "<<endl;
cout<<"\t TYPE 4 TO MODIFY"<<endl;
cout<<"\t TYPE 5 TO DELETE "<<endl;
cout<<"\t TYPE # TO QUIT "<<endl<<endl;
cin>>option;
switch(option){
case '1': rfappend(personname,phone);
break;
case '2': rfdisplay(personname,phone);
break;
case '3': rfsearch();
break;
case '4': rfmodify();
break;
case '5': rfdelete();
break;
case '#': cout<<"BYE "<<endl;
exit(1);
break ;
default: cout<<"Enter 1 to 5"<<endl;
}//SWITCH
}//WHILE
system ("Pause");
return 0;
}
 

This program will send out the input to a file called directory.in.

Binary vs. Text files

Binary files are used to store executable code, Text Files are used to store raw text from the system.
 

For Last year notes : Class notes

Name______________________________________

T / F 1) A database has operations such as storing, displaying, and searching for records.

T / F 2) A file should be closed before it is opened again for another operation mode.

T / F 3) A file can be accessed sequentially as well as randomly.

T / F 4) The most efficient way to delete from a file is to copy the entire file, excluding deleted data.

T / F 5) Random access becomes faster if each record has a fixed length with a unique key.

T / F 6) Binary files store the binary value of a number instead of its ASCII value.

T / F 7) Modification is more difficult in arrays rather than in a sequential file.

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

T / F 9) Information in an array will be lost after the program terminates.

T / F 10) In sequential files, modification requires duplication of the existing file.

T / F 11) A data file is a file in which data is stored and from which data is retrieved.

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

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

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

T / F 15) If the array is not shuffled after deletion, it is necessary to indicate that the record was deleted.

T / F 16) A Database is a collection of unrelated data.

T / F 17) One person having many credit cards is an example of a many-to-many relationship.

T / F 18) The most important function in a database is delete.

T / F 19) A database can have at most one table.

T / F 20) The importance of normalization of a database is to create more memory for redundancy of data.

 =====================================================================================

T / F 21) Simple file encryption can be done by changing ASCII values or by using an associate array.

T / F 22) Overtime pay computation is a function of select command and SQL reports are an example of database manipulation.

T / F 23) A database report is used by managers to enter new records to a database.

T / F 24) Add (append) , Delete (purge), Modify (update), and Search are all functions of operating systems.

T / F 25) The interaction between you and your computer is also known as an interface.

T / F 26) Three categories of data models are conceptual, physical, and implementation.

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

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

T / 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.

T / F 30) Creating relationships between tables increases data redundancy and makes a database less efficient.

T / F 31)  When input data becomes large, it is necessary to work with a data file rather than typing it.

T / F 33) Unicode consists of 32 bits.

T / F 34) A database consists of infinite fields.

T / F 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 / F 36) ifstream fin(“data.txt”,ios::in); if(!fin) cout<<”NO FILE”;  will test the file’s existence.

T / F 37) A file can be opened for both input and output such as fstream fout(“data.dat”, ios::in|ios::out);

T / F 38) “del” and “rename” in C++ which are to delete and rename a file, are equivalent to “rm” and “mv” which are in Linux or Unix.

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

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

T / F 41) Sequential search is preferred over hashing because of the speed.

T / F 42) The C++, system( ) function enables the programmer to use operating system commands.

T / F 43) In a random access file, seekg( ) is used for putting data and seekp( ) is used for getting data.

T / F 44) Most of today’s databases interact with the user and then access the data file to search and to perform the necessary operations.

T / F 45) A table in a relational database is a predefined format of rows and columns that define an entity.

T / F 46) Examples of databases are WindowsNT, UNIX, DB2, MYSQL, and Solaris.
 

T / F 47) You can create CGI web databases using the following programming languages: C/C++ and Perl.

T / F 48) The three example databases are Access, SQL, and Oracle.

T / F 49) In a database, a table contains records, records contain fields, fields contain characters, a character contains a byte or two.

T / F 50) Encryption is essential when working with databases to keep information unaccessible.

 =====================================================================================

T / F 51) A bite has a single binary value, either 0 or 1.
 

T / F 53)By using a linked list the deleted record will be physically deleted.

T / F 54)A relational database is a collection of organized data that are related between its

various data members.

T / F 55) A byte is the smallest addressable unit of data in a computer.

T / F 56) A database can be made in any language such as C++, Java, Visual Basic, or JavaScript.

T / F 57) The interaction between you and your computer is also known as an interface.

T / F 58) C++ is the foundation for the most popular database application on the Internet.

T / F 59) The three example databases are Adobe, PowerPoint, and Microsoft Word

T / F 60) An example of Data Manipulation\Reporting in a Payroll\Bank Database is an overtime pay report.

T / F 61) There have been as many as 9,000 deaths as a result of medical database errors each year.

T / F 62) Ingres is a database under windows operating systems.



T / F 63) Primary key is used in relational databases to uniquely identify records.

T / F 64) For a database security is more important than access.

T / F 65) Database Normalization is used to minimize duplication of information.

T / F 66) The main functions of the database are: create, read, update, duplicate, and delete.

T / F 67) A key feature of the computer is the ability to store information, and to retrieve it at a later time.

T/F 68) The important commands of SQL are select, update, and purge.

T/F 69) The Assignment for this class is to design a Web interface.

T/F 70) To create a database interface you must use Oracle.

T/F 71) In order to design a database with access it must be specified the length and type of each field.

T/F 72) In Unicode the value of 'A' is 65 and 'a' is 97.

T/F 73) It is possible to create a database on Web by using CGI.

T/F 74) The most important function of a database is the search function.

T/F 75) It is possible to retrieve deleted records from a database.

Next class we will have our first quiz. all questions by us. please Email to ebrahimidr@gmail.com  

Please have questions from all areas covered, Test will be on Monday 25th 2008 100 T/F Questions.

Most questions in this example are from chap. 9 That are important for a strong foundation of database

1- First copy and paste the questions from the website to a blank page.

2- Answer all questions and Email them to ebrahimidr@gmail.com  

3- Copy this to your wcm Exam Webpage.

Today we will discuss backing up your database.

Page 291-292 functions:

WHAT IS A DATABASE (dbase)

Manipulating data (information) plays an important role in any organization today. In order to manipulate the data, information has to be stored, retrieved, modified or deleted. At any moment new data can be added to a file, or existing information can be retrieved, modified or even deleted. Instead of one file there might be several files needed to store information as well as to interact with other files (file processing). The notion of data manipulation where data may be stored, retrieved, modified or even deleted is called a database.  In addition, there are times when it is necessary to generate reports based on a certain request or computations from the database.

A JOURNEY FROM BIT TO DATABASE

Computer information is represented in binary form using a bit.  Each bit contains a value which is either zero or one. Eight bits represent a byte. Depending on the system one or two bytes represent a character. Several characters form a field or a string. One or more fields make up a record. Multiple records build a stream or a file. Finally several files create a database. However this naming convention may vary slightly, a string may represent the whole file or a database may contain only a single file.

BUILDING A SIMPLE DATABASE: Create, Display and Search

The following program illustrates how easily you can build a simple database by putting a few functions together. For the sake of simplicity, the database program will add, display and search the data immediately, with data modification and deletion performed later. In writing this program, the concern is simplicity rather than efficiency (speed of program or saving space). The three functions for this database are myappend() to add a record to the end of data file, mydisplay() to display entire records, and mysearch() to search  for a particular record.

MODE OF OPENING A FILE

A file can be opened according to the following ways (modes):

A file can be opened as an input file so that data can be retrieved.

ifstream fin (“data.in”,ios::in);

 The default file mode for ifstream is ios::in

ifstream fin (“data.in”); //input stream

A file can be opened so that data can be written or output to it.

ofstream fout (“data.out”,ios::out);

  The default file mode for ofstream is ios::ou

ofstream fout (“data.out”);

In addition a file can be for output by adding (appending) data to the end of the existing file.

ofstream fout (“data.out”,ios::app);

A file can be for both input and output ios::in | ios::out

fstream fout (“data.dat”, ios::in|ios::out);

Ruan  contribution for today program from page 292.

#include<fstream>

#include<string.h>

#include<iostream>

#include<iomanip>

#include<stdlib.h>

using namespace std;

int myappend(char personname[],char phone[]){

ofstream fout("directory.txt",ios::app);

cout<<"ENTER PERSON NAME";

cin>>personname;

cout<<"Enter THE PHONE";

cin>>phone;

fout<<personname<<setw(20)<<phone<<endl;

return 0; }// MyAppend

int mysearch(char personname[],char phone[]){

char searchname[20];

ifstream fin("directory.txt",ios::in);

cout<<"ENTER THe Search Name";

cin>>searchname;

while(fin>>personname>>phone){

if(strcmp(searchname,personname)==0){

cout<<"THE PHONE IS" <<phone<<endl<<endl;

return 1; } //if

}// while

cout<<"NAME NOT FOUND" <<endl;

return 0; } //MYSearch

int mydisplay(char personname[],char phone[]){

ifstream fin("directory.txt");

while(fin>>personname>>phone){

cout<<"PERSON NAME IS" << personname<<endl;

cout<<"PHONE IS " <<phone<<endl; }//while

return 0; } // My Display

main(){

char option;

char personname[20],phone[20];

cout<<"Select One Of The Following" << endl;

while(1) { cout<<"TYPE 1 TO INSERT" <<endl;

cout<<"TYPE 2 TO Display" <<endl;

cout<<"TYPE 3 TO Search" <<endl;

cout<<"TYPE # TO Quit" <<endl;

cin>>option;

if(option =='1')myappend(personname,phone);

else if (option=='2') mydisplay(personname,phone);

else if (option=='3') mysearch(personname,phone);

else if (option=='#') {cout<<"BYE"<<endl;exit(1);} } //while

return 0;

}//Main

 

 YEAR 2007 NOTES Class notes

Journal Wednesday February 13, 2008

Please have questions from all areas covered, Test will be on Monday 25th 2008 100 T/F Questions.

Most questions in this example are from chap. 9 That are important for a strong foundation of database

This is an example of last years test please try to use all topics covered in the semester.

BU 5010 Database Applications for Managers                                                            

Quiz 1 True / False                                                                                                        Spring 2007

Name______________________________________

T / F 1) A database has operations such as storing, displaying, and searching for records.

T / F 2) A file should be closed before it is opened again in another operation mode.

T / F 3) A file can be accessed sequentially as well as randomly.

T / F 4) The most efficient way to delete from a file is to copy the entire file, excluding deleted data.

T / F 5) Random access becomes faster if each record has a fixed length with a unique key.

T / F 6) Binary files store the binary value of a number instead of its ASCII value.

T / F 7) Modification is more difficult in arrays rather than in a sequential file.

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

T / F 9) Information in an array will be lost after the program terminates.

T / F 10) In sequential files, modification requires duplication of the existing file.

T / F 11) A data file is a file in which data is stored and from which data is retrieved.

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

Answer: True there is no need for duplication.

- Give me one example of deleting a file of database and why?

 Answer: A student must be deleted from active students after they graduated

- If you have a  cassette tape containing two song and you need to delete song one how will you do it?

Answer: copy the song one into a blank cassette tape, if you deleted  from the tape you would have a blank gap for the length of the song.

What is a Random Access?

Answer: A CD is a random access

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

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

T / F 15) If the array is not shuffled after deletion, it is necessary to indicate that the record was deleted.

T / F 16) A Database is a collection of related data.

T / F 17) One person having many credit cards is an example of a many-to-many relationship.

T / F 18) The most important function in a database is delete.

T / F 19) A database can have at most one table.

Answer: False - At least one table

T / F 20) The importance of normalization of a database is to eliminate waste of memory and redundancy of data.

T / F 21) Simple file encryption can be done by changing ASCII values or by using an associate array.

Answer: True The sensitive material should always be encrypted. This is Part of Internet security.

ASCII American Standard Code for Information Interchange

T / F 22) A data file is an executable file that performs a database function.

T / F 23) A database report is used by managers to enter new records to a database.

T / F 24) A Database Designer’s responsibility is to define the content, the structure, the constraints, and functions or transactions against the database.

T / F 25) A set of concepts to describe the structure and the constraints of a database is called a data object.

T / F 26) Three categories of data models are conceptual, physical, and implementation.

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

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

T / 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.

T / F 30) Creating relationships between tables increases data redundancy and makes a database less efficient.

T / F 31)  The proper C++ code to open a text file is:

T / F 32) In C++, the syntax code if (!fin) can be used instead of if (fin==NULL). 

T / F 33) Unicode consists of 8-16 bits.

T / F 34) A database consists of many fields.

T / F 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 / F 36) ifstream fin(“data.txt”,ios::in); if(!fin) cout<<”NO FILE”;  will test the file’s existence.

T / F 37) A file can be opened for both input and output such as fstream fout(“data.dat”, ios::in|ios::out);

T / F 38) ofstream outfile(“data.txt”, ios::noreplace);  prevents an existing file from being overwritten.

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

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

T / F 41) Sequential search is preferred over hashing because of the speed.

T / F 42) The C++ system( ) function enables the programmer to use operating system commands.

Answer:

 This are some known operating systems Windows , Solaris Sparc, Solaris Intel , QNX , OS/2 , MacOS , Linux Sparc, Linux PowerPC, Linux i386, FreeBSD i386 , BeOS
 

T / F 43) In a random access file, seekg( ) is used for putting data and seekp( ) is used for getting data.

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

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

T / F 46) ifstream fin(“data.txt”, ios::in); associates a file for output access.

T / F 47) You can create CGI web databases using the following programming languages: C/C++ and Perl.

T / F 48) The three example databases are Access, SQL, and Oracle.

T / F 49) In order for a C++ database program to read from a textfile it is not necessary to use; #include<fstream>.

T / 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.

T / F 51) A software package/ system to facilitate the creation and maintenance of a computerized database is known as DBA.

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

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

T / F 58) The Entity Relationship Model consists of entities with no possible relation to each other.

T / F 59) In the Object Oriented Model, objects consist of data operations on the data.

T / F 60) The physical implementation of your database files at the lowest level is specified at the conceptual level.

In fall 2004, computers were about 8 times more powerful.

Estimated number of computers for 250 million searches per day:

       = (250/5.5) x 2,500/8

       = about 15,000

Some industry estimates (based on Google's capital expenditure) suggest that Google and Yahoo may have had as many as 250,000+ computers in fall 2007.

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