1. Primary Key:
(i) This key of relational table identifies each record in the table in a unique way.
(ii) A primary key which is a combination of more than one attribute is called a composite primary key.
(iii) The candidate key that is chosen to perform the identification task is called the primary key
2. Foreign Key:
(i) A foreign key is a "copy" of a primary keythat has been exported from one relation into another to represent the existence of a relationship between them
(ii) A foreign key is a copy of the whole of its parent primary key i.e if the primary key is composite, then so is the foreign key.
(iii) Foreign key values do not (usually) have to be unique.
(iv) Foreign keys can also be null.
(v) A composite foreign key cannot have some attribute(s) null and others non-null.
3. Candidate Key:
(i) Each super key is called a candidate key.
(ii) A candidate key is selected from the set of Super Key.
(iii) While selecting candidate key, redundant attributes should not be taken.
(iv) The candidate key is also known as minimal super keys.
4. Super Key:
(i) An attribute or group of attributes, which is sufficient to distinguish every tuple in the relation from every other one is known as Super Key.
5. Composite Key (Compound Key):
(i) A key with more than one attribute to identify rows uniquely in a table is called Composite key.
(ii) This is also known as Compound Key.

(i) Tampering intentional modification of products in a way that would make them harmful to the consumer
(ii) E-Commerce has the problem of the authenticity and integrity of business information.
(iii) When hackers grasp the data transmitted on the network, it can be falsified in the middle through various technical means, and then sent to the destination, thereby destroying the authenticity and integrity of the data.

1. File upload is the best feature to select one file from the local machine to server machine.
2. Form tag is used to mention a method as POST or GET and encrypt attribute mentioned as "multipart/form-data".
3. In the < Input > tag mention type="file" attribute shows the input field as a file-select control, with a "Browse" button next to the input control.
4. The form above sends data to a file.
5. In Server machine "php.ini" file, search for the file_uploads directive, and set it to On: "file_uploads = On"
6. After submitting the upload button the request reaches to the file.
7. In the file ＄FILES variable collects all uploaded file information such as name of the file, size of the file and extension of the file etc.
8. All the details are checked thoroughly and the errors are saved in an array variable.
9. The file finally moves under the image directory if the array error variable is empty.

(i) Third generation of mobile systems merges different mobile technology standards, and uses higher frequency bands for transmission and Code Division Multiple Access to delivery data rates of up to 2Mbit/s supports multimedia services (MMS: voice, video and data) .
(ii) European standard is UMTS(Universal Mobile Telecommunication Systems).
(iii)  Mobile phones systems continue to use digital transmission with SIM authentication for billing systems and for data incorruption.
(iv) Data transmission used a WCDMA. WCDMA stands for (Wideband Code Division Multiple Access).
(v) One technique to obtain data rates between 384kbit/s and 2048kbit/s. Few 3G suppliers use ATM (Asynchronous Transfer Mode) for their 'over the air' network with in MPLS(Multiprotocol Label Switching) or IP for theirs backbone network.
(vi) Mobility still supported at layer2, and hence like 2G it still prohibits seamless roaming beyond heterogeneous access networks and routing domains.
(vii) The transmission were band frequencies are between 1900 and 2200 MHz. All UMTS license holders at the UK holds a 20-year license with the condition that 80% population coverage is achieved by 31 December 2007.
(viii) The present third generation licensed operators in the UK can be seen below as at August 2004.

< ?php
＄n = "February";
switch(＄n) {
case "January":
echo "Its January";
break;
case "February":
echo "Its February";
break;
case "March":
echo "Its- March";
break;
case "April":
echo "Its April";
break;
case "May":
echo "Its May";
break;
case "June":
echo "Its June";
break;
case "July":
echo "Its July";
break;
case "August":
echo "Its August";
break;
case "September":
echo "Its September";
break;
case "October":
echo "Its October";
break;
case "November":
echo "Its November";
break;
case "December":
echo "Its December";
break;
default:
echo "Doesn't exist";
}
? >

(i) Four Parameters are used to connect to the Database server.
(ii) They are
1.＄ servername -> Database Server server IP address
2.＄ susername -> Database Server User Name
3.＄ password -> Database Server Password
4.＄ DB_Name -> Database Name

Credit card is an electronic payment system normally used for retail transactions. A credit card enables the bearer to buy goods or services from a vendor, based on the cardholder's promise to the card issuer to payback the value later with an agreed interest. Every credit card account has a purchased limit set by the issuing bank or the firm. A credit card is different from a debit card where the credit card issuer lends money to customer instead of deducting it from customer's bank account instantly.
Key players in operations of credit card:
Bearer: The holder of the credit card account who is responsible for payment of invoices in full (transactor) or a portion of the balance (revolver) the rest accrues interest and carried forward.
Merchant: Storekeeper or vendor who sell or providing service, receiving payment made by its customers through the credit card.
Acquirer: Merchant's bank that is responsible for receiving payment on behalf of merchant send authorization requests to the issuing bank through the appropriate channels.
Credit Card Network: It acts as the intermediate between the banks. The Company responsible for communicating the transaction between the acquirer and the credit card issuer. These entities operate the networks that process credit card payments worldwide and levy interchange fees.
E.g. Visa, MasterCard, Rupay
Issuer: Bearer's bank, that issue the credit card, set limit of purchases, decides the approval of transactions, issues invoices for payments, charges the holders in case of default and offer card- linked products such as insurance, additional cards and rewards plan.
Advantages of credit card:
1. Most credit cards are accepted worldwide.
2. It is not necessary to pay physical money at the time of purchase. The customer gets an extra period to pay the purchase.
3. Depending on the card, there is no need to pay annuity.
4. Allows purchases over the Internet in installments.
5. Some issuers allows "round up" the purchase price and pay the difference in cash to make the transactions easy.

An operator is a symbol that performs a given action on a value or group of values. The values the operation is performed upon are known as operands.
The types of operators in PHP are
(i) Arithmetic operators
(ii) Assignment operators
(iii) Comparison operators
(iv) Increment/Decrement operators
(v) Logical operators and
(vi) String operators
1. Arithmetic operators
Arithmetic operators are used to perform math operations, for example, addition, subtraction, multiplication, and division.

Operator	Operator Name	Example	Output
+	Addition	5+2	7
-	Subtraction	5-2	3
*	Multiplication	5*2	10
/	Division	5/2	2.5
%	Modulus	5%2	1

2. Assignment operators
The assignment operator is used to assign a value to a variable. The assignment operator takes the value of its right-hand operand and assigns it to its left-hand operand.

Operator	Operator Name	Example	Output
=	Assignment operator	$a = 5;	5

3. Comparison operators
Comparison operators are used to compare two values and determine whether a certain condition is true or false.

Operator	Operator Name	Example	Output
>	Greater than	5 > 2
<	less than	5<2	False
>=	Greater than or equal to	5>= 2	True
<=	Less than or equal to	5<=2	False
==	Equal to	5==5 5 == 5.0	True False
===	Identical	5===5 5===5.0	True False
!=	Not equal	5!=5 5!=6	True False
!==	Not identical	5!==5 5!==5.0	True False

4.Logical Operators:
Logical operators are used to perform logical operations on variables and values.

Operator	Operator Name	Example	Output
&&	Logical AND	(5>3) && (5>7)	False
II	Logical OR	(5>3) II (5>7)	True
xor	XOR	(5>3) xor (5>7)	True
!	Logical NOT	! (5>3)	False

5. Increment and Decrement operators
In PHP, the increment operator ++ is used to increase the value of a variable by 1, and the decrement operator is used to decrease the value of a variable by 1. The increment and decrement operators can be used as either prefix or postfix operators.

Operator	Name	Output
++ (increment operator)	++ $a Pre-increment	$x = ++ $a
++ (increment operator)	$a + + Post-increment	$x = $a ++
-- (decrement operator)	--$a Pre-decrement	$x = --$a
-- (decrement operator)	$a-- Post-decrement	$x = $a--

6. String operator

String operators have concatenation operator(.) and concatenation assignment operator(-). Concatenation means adding one or more variables to an existing variable.

Operator	Name	Example	Output
. (Dot)	Concatenation	$a = 'Hello'; $b = 'World'; $c= $a. $b;	Hello World
.= (Dot equal to)	Concatenation	$a= 'Hello': $b = 'World'; $a .= $b;	Hello World

Drawing a star using polygon tool.
To draw a Star
(i) Click on the Polygon tool from the toolbox. The cursor changes to a crosshair.
(ii) Click and drag anywhere on the screen. As you drag, a Polygon appears.
(iii) Release the mouse button when the Polygon is of the desired size.
(iv) Choose Element →  Polygon settings in the menu bar. Now polygon settings dialogue box appears.
(v) Type 5 in the Number of sides text box.
(vi) Type 50% in star inset textbox.
(vii) Click OK. Now the required star appears on the screen.

Multimedia is the presentation of computer controlled and interactive information using the combination of video, sound, text, pictures and animations.
Steps in Multimedia Production :
i) Conceptual Analysis and Planning
ii) Project Design
iii) Pre Production
iv) Budgeting
v) Multimedia Production Team
vi) Hardware/Software Selection
vii) Defining the Content
viii) Preparing the Structure.
ix) Production
x) Testing
xi) Documentation
xii) Delivering the Multimedia Product
(i) Conceptual analysis identifies a appropriate theme, budget and content availability on that selected projects.
(ii) Project design phase contribute the series of actions performed to implement an objective.
(iii) Based on the planning and design, Budgeting, Hardware / Software selection and the content are necessary to develop the project.
(iv) Production team responsible for script writing, editing, graphics, etc.
(v) Complete the testing of the pilot product before the mass production.
(vi) User documentation is a mandatory feature for all multimedia projects.
(vii) Finally, multimedia application is delivered in more effective way by the integration of two mediams CD-ROM/DVD and Internet.

A method of scrambling data using an algorithm to protect / hide from un authorized access

Single mode ((100 Base Bx)) and Multimode((100 Base SX))

(i) XAMPP is a free and open source package.
(ii) It was developed by Apache.
(iii) It is a software platform for MySQL, PHP and Peri programming languages.

1. Click on View. The View menu will appear.
2. Click on Hide Rulers to hide the rulers.

Information's are available in digital formats that include digital books, scanned images, graphics and digitized audio-visual clips etc stored in Digital Multimedia Library

Packet switching is used to transfer the information between computers and network

MySQLi is extension in PHP scripting language which gives access to the MYSQL database.

A significant output of simulation is the trace files. Trace files can document every incident that happened in the simulation and are used for examination.

(i) Variable name must always begin with a \($\) symbol.
(ii) Variable name can not start with a number.
(iii) Variable names are case-sensitive. Eg. \($\)a = 6;

(i) Remix
(ii) Remake
(iii) Remanufacture
(iv) Redistribute
(v) Resell
(vi) Study and Learn

Few major functions performed using SQL are listed below:
(i) Executes queries against a database.
(ii) Retrieves data from database.
(iii) Inserts and updates records in a database
(iv) Delete records from database
(v) Creates new databases and new tables in a database

1. PHP Parameterized functions are the functions with parameters or arguments.
2. The parameter is also called as arguments, it is like variables.
Rules:
1. The arguments are mentioned after the function name and inside of the parenthesis.
2. There is no limit for sending arguments, just separate them with a comma notation.

(i) The mysqll_connect function uses these variables and connect Database server from PHP scripting.
 (ii) If connection gets fail, output will be printed with MySQL error code. Otherwise connection is success.

Character	Uses
Apostrophe (')	segment terminator
Plus sign (+)	segment tag and data element separator
Colon (:)	component data element separator
Question mark (?)	Release character
Period (.)	decimal point.

(i) To get form data, we need to use PHP $_GET and S_POST.
(ii) To retrieve data from get request, we need to use $_GET and for post request $_POST.
(iii) We can send limited amount of data through get request and large amount of data through post request.

1. Do whileloop always run the statement inside of the loop block at the first time execution.
2. Then it is checking the condition whether true or false.
3. It executes the loop, if the specified condition is true.
Syntax:
do
{code to executed;
}while (condition is true);

Switch Statement	If else statement
Switch statement uses single expression for multiple choices.	if-else statement uses multiple statement for multiple choices.
It test only for equality.	It test for equality as well as for logical expression.
Statement will be executed is decided by user.	Evaluates any type
If switch statements does not match any cases, the default statements is executed.	If the condition fails, then by default the else statement is executed.

Basis for comparison	Server-side scripting	Client-side scripting
Basic	Works in the back end which could not be visible at the client end.	Works at the front end and script are visible among the users.
Processing	Requires server interaction	Does not need interaction with the server
Languages involved	PHP, ASP.net,Ruby on Rails, ColdFusion, Python, etcetera.	HTML, CSS, JavaScript, etc.
Affect	Could effectively customize the web pages and provide dynamic websites	Can reduce the load to the server.
Server-side scripting	Relatively secure.	Insecure