U:/msu/course/cse/103 Day 21, Slide 1 CSE 103 Makeups –If you didn’t take one over the weekend, take one TUESDAY or WEDNESDAY! –Next chance: take one between FRIDAY and TUESDAY But don’t take one during the game(s); that would be lousy –In-class BT: next THURSDAY (or MONDAY, April 11)

U:/msu/course/cse/103 Day 21, Slide 2 Dynamically Generated Web Pages Dynamic web pages are generated as needed or as requested Allows you to make a huge number of pages from a single file using a “scripting language” such as PHP

U:/msu/course/cse/103 Day 21, Slide 3 Client requests The web server requests data from the database server based on the PHP script Database Server Web Server Serving PHP files that use a database

U:/msu/course/cse/103 Day 21, Slide 4 PHP and databases PHP connects to MySQL –Other database servers also supported Specify which database to connect to –Today we'll use the movies database Store queries in the PHP file –Web server sends them to database server –Database server sends results back Today we will start making a small “cast browser” set of pages

U:/msu/course/cse/103 Day 21, Slide 5 CSE 103 functions To simplify using PHP, we provide some common utilities for you –Can use require() just like include() in order to use a library –Functions in that file can be called from the requiring file –They save you time; not having to learn picky details about PHP –Feel free to examine the source code (Day 21 AFS) Start a new PHP page named actor.php in Dreamweaver. (Save in your web folder!) Include the function definitions from the file above by entering at the top of your new page (line 1) <?php require('/afs/msu/course/cse/103/php/cse103.php');?>

U:/msu/course/cse/103 Day 21, Slide 6 Test database connection Use set_database() to choose the database with –Server: "cse103.egr.msu.edu" –Database: "movies" –Username: "yourmsuNetID" –Password: "yourPID", with starting A capitalized Add the PHP function get_SQLversion() to the page in a print statement in the Add the PHP function get_SQLversion() to the page in a print statement in the –This function finds the version of the MySQL database server being used (4.1.8a-Debian_1-log) Test the page by browsing to it:

U:/msu/course/cse/103 Day 21, Slide 7 Variables in PHP Variables and constants let you store values for later use –The “value” of variables can change All PHP variables begin with a $ followed by a non-numeric character –Example: $name = 'Bob'; –Assigns the value Bob to the variable $name Only alphabetic, numeric, and _ characters are allowed in variable names

U:/msu/course/cse/103 Day 21, Slide 8 Query strings An SQL query is usually several lines long It is usually entered as a single string–in "quotes" It is usually assigned to a variable, so that it can easily be passed to functions The query itself should NOT end with ; but the PHP statement MUST end with one (OUTSIDE the quotes around the query) Example: $query = "SELECT MovieTitle, Year FROM tbl_Movies WHERE Year = 2004";

U:/msu/course/cse/103 Day 21, Slide 9 Using a query to generate a dynamic page Create an SQL query that finds FirstName and LastName of a person identified by ActorID –Use ActorID= to test the query Store this (and every query you ever use) in a variable Use print and the text_from_query() function to display the actor’s name –Check the Day 21 classwork page for documentation link

U:/msu/course/cse/103 Day 21, Slide 10 Using a query to generate a dynamic table Create a second SQL query that finds each movie, year, and role in which s/he has appeared – ordered by year –Continue to restrict by ID number Make a table on your page of the results of this query using print and table_from_query() –Check the support function documentation linked from the Day 21 page if you need to –Very similar to using text_from_query()

U:/msu/course/cse/103 Day 21, Slide 11 Movie information Create a new PHP page called movie.php Display name & year of movie (given MovieID) as a heading on the page (in tags) –Test with MovieID = Make a table displaying each credit number*, role in the movie, and name of actor playing it –Order by CreditNumber (*this field is in tbl_Roles) –Use the MySQL concat() function to put both first and last name of the actor into a single field

U:/msu/course/cse/103 Day 21, Slide 12 Passing information to a dynamic page Parameters can be passed in a URL Example: –…/actor.php?ActorID= Same syntax can be used by forms in a GET operation –We will look at this next time

U:/msu/course/cse/103 Day 21, Slide 13 Using parameters in PHP Each parameter becomes a special PHP variable, of the form $_GET['key']=value, where key is the name before = and value is after: –…/actor.php?ActorID=1234 makes $_GET['ActorID']=1234 –Key is case-sensitive: $_GET['actorid']=0 This value can be used later in PHP If you need to use it inside a quoted string, like a query, put curly braces { } around it: $query = "…WHERE ActorID={$_GET['ActorID']} …";

U:/msu/course/cse/103 Day 21, Slide 14 Exercise - Using parameters in PHP Modify the actor.php page to GET the value of ActorID from a parameter Change your queries to use the correct $_GET['xyz'] variable Test cases: –ActorID= is Sandra Bullock and ActorID= is Keanu Reeves

U:/msu/course/cse/103 Day 21, Slide 15 Exercise – Using parameters again Now modify the movie.php page to GET the value of MovieID from a parameter Change your queries to use the correct $_GET['xyz'] variable Test cases: –MovieID= is Star Wars III and MovieID= is Robots

U:/msu/course/cse/103 Day 21, Slide 16 Homework Check the link on today’s classwork page –Finish classwork –Read rest of Day 20 textbook, covering HTML forms –Work on UBTs!