CSCI-UA: Database Design & Web Implementation. Professor Evan Sandhaus

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1 CSCI-UA: Database Design & Web Implementation Professor Evan Sandhaus Lecture #18: PHP: The PHP Hypertext Preprocessor Database Design and Web Implementation

2 Database Design and Web Implementation 2

3 3 Database Design and Web Implementation

4 4 Database Design and Web Implementation

5 Administrivia Midterm - Couple of you don t have it Homework Homework 6 due 4/9/2013 Database Design and Web Implementation 5

6 On The Menu (re)introduction To PHP (re)introduction To HTML Forms HTML Forms + PHP = Awesome Sauce Return to SQL Queries (Time Permitting) Database Design and Web Implementation 6

7 PHP PHP = The PHP Hypertext Preprocessor Invented in 1995 Server Side Scripting Language (deets on next slide) Running on 244 Million Websites Evan Sandhaus is not a huge fan Database Design and Web Implementation 7

8 PHP - Server Side Scripting Language Database Design and Web Implementation 8

9 Up and running with PHP at NYU Create a PHP File Put in somewhere on i6 that is web-accessible. Make sure the file and directory are world executable chmod 755 <file dir> Access that PHP File in your browser Profit (not really) Gory Details: CSCI-UA /Php_on_i6_sp13.php Database Design and Web Implementation 9

10 PHP - Hello World <?php?> echo "Hello World!"; OR <?php?> print "Hello World!"; Database Design and Web Implementation 10

11 PHP - Variables // numbers $current_year = 2013; $pi = ; $distance_to_moon = 3.844e6; Database Design and Web Implementation 11

12 PHP - Variables // booleans $just_true = true; $just_false = false; $or_true = $just_true $just_false; // true $and_true = $just_true && $just_true; //true Database Design and Web Implementation 12

13 PHP - Variables // Strings $single_quotes = 'Single Lady'; $double_quotes = "By Beyonce"; // String Concatenation $concat = $single_quotes." ".$double_quotes; // "Single Lady By Beyonce" // String Formatting $formatted_string = "Welcome to $current_year!"; // "Welcome to 2013" $format_fail = 'Welcome to $current_year!'; // "Welcome to $current_year" $format_comma = 'Welcome to '.number_format($current_year); // "Weclome to 2,013" Database Design and Web Implementation 13

14 PHP - Arrays // Arrays // creates an empty array $simple_array = array(); // set position 0 to 1 $simple_array[0] = 1; // create an array with the specified values $simple_array = array( 1,2,3,5,7,11,13 ); // append 17 to the end of the array $simple_array[] = 17; // assign value 5 to $a_prime $a_prime = $simple_array[3]; // assign length of $simple_array (8) to $a_length $a_length = sizeof($simple_array); Database Design and Web Implementation 14

15 PHP - Dictionaries // Dictionaries - also arrays // but with keys that aren't sequential integers // create an empty array $simple_dictionary = array(); // assign value 'Engel' to key 'Deena' $simple_dictionary['deena'] = 'Engel'; // Inline dictionary declaration $simple_dictionary = array( 'Evan' => 'Sandhaus', 'Tara' => 'Bobiak' ); // Assigns 'Sandhaus' to $lname $lname = $simple_dictionary['evan']; // Assign "Mr. Sandhaus plans to mary Ms. Bobiak" // to $array_concat $array_concat = "Mr. {$simple_dictionary['evan']} plans to mary Ms. {$simple_dictionary['tara']}"; Database Design and Web Implementation 15

16 PHP Complex Dictionaries // assign all of the variables we've already // defined to one big array $complex_dictionary = array( 'current_year' => $current_year, 'pi' => $pi, 'distance_to_moon' => $distance_to_moon, 'just_true' => $just_true, 'just_false' => $just_false, 'or_true' => $or_true, 'and_true' => $and_true, 'single_quotes' => $single_quotes, 'double_quotes' => $double_quotes, 'concat' => $concat, 'formatted_string' => $formatted_string, 'format_fail' => $format_fail, 'format_comma' => $format_comma, 'simple_array' => $simple_array, 'a_prime' => $a_prime, 'a_length' => $a_length, 'array_concat' => $array_concat, 'simple_dictionary' => $simple_dictionary, 'lname' => $lname, ); Database Design and Web Implementation 16

17 Foreach Loops $simple_dictionary = array( 'Evan' => 'Sandhaus', 'Tara' => 'Bobiak' ); // Simple foreach loop // Prints out // Evan Sandhaus // Tara Bobiak foreach ($simple_dictionary as $key => $value) { echo "$key $value<br>"; } echo "<br>"; Database Design and Web Implementation 17

18 PHP Built-In Fuctions is_array(x), is_boolean(x), is_string(x) : True if x is of the specified type. implode(glue, array) create a string containing each of the elements from array separated by the 'glue' string. isset(array[key]): Returns true if key exists in array, false otherwise. sizeof(array), count(array): Return the size of an array. Database Design and Web Implementation 18

19 Foreach Loop And Conditionals // print out all of our example variables foreach ($complex_dictionary as $key => $value) { if (is_array($value)) { // if the value is an array format it nicely $array_string = '['.implode(', ', $value).']'; echo "<b>$key:</b><br>'$array_string'<br><br>"; } else if (is_string($value)) { // If the value is a string put quotes around it. echo "<b>$key:</b><br>'$value'<br><br>"; } else if (is_bool($value)) { // If the value is a boolean render it as // True or False $boolean_string = ($value)? 'True' : 'False'; echo "<b>$key:</b><br>$boolean_string<br><br>"; } } else { // If the value is anything else // just throw it in to the mix echo "<b>$key:</b><br>$value<br><br>"; } Database Design and Web Implementation 19

20 Example PHP In HTML Printout All of the Current Date and The Browser and the Remote Host $_SERVER['REMOTE_HOST'] $_SERVER['HTTP_USER_AGENT'] $date('y/m/d H:i:s'); Database Design and Web Implementation 20

21 HTML Form Review Lets Create a form for submitting a news article to a CMS. Fields Headline Byline Type of Material "News / Opinion" Bureau - Drop Down Article Database Design and Web Implementation 21

22 Form <form action="cms.php" method="post" > Database Design and Web Implementation 22

23 Inputs <input type="text" name='headline'/> <select name='issue'> <option value='winter'>winter</option> <option value='spring'>spring</option> <option value='summer'>summer</option> <option value='fall'>fall</option> </select> Database Design and Web Implementation 23

24 Inputs Continued <input type='radio' name='content_type' value='news'>news</input> <input type='radio' name='content_type' value='opinion'>opinion</input> <textarea rows="10" cols="60" name='article_body'></textarea> <input type="checkbox" name="tag[]" value="us">united States<br> <input type="checkbox" name="tag[]" value="world">world<br> <input type="checkbox" name="tag[]" value="sports">sports<br> <input type="checkbox" name="tag[]" value="entertainment">entertainment<br> Database Design and Web Implementation 24

25 Submit <input type="submit" value="submit"> Database Design and Web Implementation 25

26 Tying it all togeather <!DOCTYPE html> <html> <head> <title>fake CMS Form</title> </head> <body> <form name="cms_input" action="cms.php" method="post" class='pretty_form'> <p> Headline:<br> <input type="text" name='headline'/> </p> <p> </p> <p> </p> <p> </p> <p> </p> <p> </p> Byline:<br> <input type="text" name='byline'/> Issue: <select name='issue'> <option value='winter'>winter</option> <option value='spring'>spring</option> <option value='summer'>summer</option> <option value='fall'>fall</option> </select> Content Type:<br> <input type='radio' name='content_type' value='news'>news</input> <input type='radio' name='content_type' value='opinion'>opinion</input> Article Text:<br> <textarea rows="10" cols="60" name='article_body'> </textarea> Tags:<br> <input type="checkbox" name="tag[]" value="us">united States<br> <input type="checkbox" name="tag[]" value="world">world<br> <input type="checkbox" name="tag[]" value="sports">sports<br > <input type="checkbox" name="tag[]" value="entertainment">entertainment<br> <p> </p> </form> </body> </html> <input type="submit" value="submit"> Database Design and Web Implementation 26

27 Database Design and Web Implementation 27

28 Query Me This How many tags are there of each type? How many authors are there of each type? Find the article with the most images? Find the article with the most tags? Find the most commonly applied tag? How many articles are authored by more than one author? How many articles are authored by organizations services? Database Design and Web Implementation 28