Princess Nourah bint Abdulrahman University. Computer Sciences Department

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1 Princess Nourah bint Abdulrahman University Computer Sciences Department 1

2 And use

3 PHP Part 3

4 Objectives Creating a new MySQL Database using Create & Check connection with Database that has been created. Creating a new table Form Handling GET vs. POST methods Insert, select, delete, update data Computer Sciences Department 4

5 Creating a new MySQL Database Computer Sciences Department 5

6 Step 1 After WAMP server has started, you will see the WAMP icon as shown below in the notification area at the bottom-right side of the desktop. If the icon is green as shown above, all services like Apache, MySQL etc. are running. If the icon is not green, left-click on it. You will see the WAMP administrator panel as shown below. Click on Start All Services. Computer Sciences Department 6

7 Step 2 Click on phpmyadmin under the Tools section. Log in with Username and Password for MySQL. Generally, the Username is "root" with no Password required for the Super user of MySQL Computer Sciences Department 7

8 Step 3 create a new Database Note: Don't use a dot(. ) in the database name Computer Sciences Department 8

9 Step 4 create a new Table Computer Sciences Department 9

10 Step 5 Create new field Computer Sciences Department 10

11 Step 6 Insert, delete, or modify etc. date Computer Sciences Department 11

12 Create a form example Computer Sciences Department 12

13 PHP 5 Form Handling When the user fills out the form.and clicks the submit button, the form data is sent for processing to a PHP file named?????????.php". The form data is sent with the HTTP POST method. Computer Sciences Department 13

14 Step 7 create a form <form action="insert.php" method="post"> ID: <input type="text" name="id"> Name: <input type="text" name="name"> Date: <input type="text" name="date"> <input type="submit"> </form> Computer Sciences Department 14

15 GET vs. POST Both GET and POST create an array (e.g. array( key => value, key2 => value2, key3 => value3,...)). This array holds key/value pairs, where keys are the names of the form controls and values are the input data from the user. $_GET is an array of variables passed to the current script via the URL parameters. $_POST is an array of variables passed to the current script via the HTTP POST method Computer Sciences Department 15

16 When to use GET? Information sent from a form with the GET method is visible to everyone (all variable names and values are displayed in the URL). GET also has limits on the amount of information to send. The limitation is about 2000 characters. However, because the variables are displayed in the URL, it is possible to bookmark the page. This can be useful in some cases. GET may be used for sending non-sensitive data. Note: GET should NEVER be used for sending passwords or other sensitive information! Computer Sciences Department 16

17 Step 8 Create & Check connection with Database $user = 'root'; $pass = ''; $db = 'db_test'; $hostname = 'localhost'; // Create connection $con=mysqli_connect($hostname,$user, $pass, $db); // Check connection if (mysqli_connect_errno()) { echo "Failed to connect to DataBase: ". mysqli_connect_error(); } Computer Sciences Department 17

18 When to use POST? Information sent from a form with the POST method is invisible to others (all names/values are embedded within the body of the HTTP request) and has no limits on the amount of information to send. Moreover POST supports advanced functionality such as support for multi-part binary input while uploading files to server. However, because the variables are not displayed in the URL, it is not possible to bookmark the page. Computer Sciences Department 18

19 PHP 5 Form Validation Explanation Computer Sciences Department 19

20 PHP 5 Forms - Required Fields When some fields cannot be empty and must be filled out in the HTML form. if (empty($_post["name"])) { $nameerr = "Name is required"; } else { $name = test_input($_post["name"]); } Example Computer Sciences Department 20

21 Insert, select, delete, update data Computer Sciences Department 21

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24 PHP Select Data From MySQL The SELECT statement is used to select data from one or more tables SELECT column_name(s) FROM table_name or we can use the * character to select ALL columns from a table: SELECT * FROM table_name Computer Sciences Department 24

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26 PHP Delete Data From MySQL The DELETE statement is used to delete records from a table DELETE FROM table_name WHERE some_column = some_value Computer Sciences Department 26

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28 PHP Update Data in MySQL The UPDATE statement is used to update existing records in a table UPDATE table_name SET column1=value, column2=value2,... WHERE some_column=some_value Computer Sciences Department 28

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