Assignment help PHP MySQL crash course

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Assignment help PHP MySQL crash course

• Gyozo Gidofalvi

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Assignment

• Implement a movie database with a web front-end
  using the Linux-Apache-MySQL-PHP, or LAMP, Web
  development framework
• To be completed in groups (3-5)
• Deploy solution
• See me in the lab to get a MySQL account for your
  group
• Demo your solution during the scheduled labs

3
Connecting to MySQL from PHP

• lt?
• link mysql_connect(hostname, username,
  password)
• or die("Could not open connection to
  database")
• ?gt
• Now the variable link contains the information
  for your connection to MySQL. You can disconnect
  using
• lt?
• mysql_close(link)
• or die("Could not close connection to
  database")
• ?gt

4
Select a database, issue queries

• Once you have connected successfully, you should
  select the database you will use. Then you can
  issue queries to the database.
• lt?
• mysql_select_db(ecomXXXX", link)
• or die("Could not select database")
• result mysql_query("select from
  some_table")
• or die("Could not issue MySQL query")
• ?gt
• Now the variable result will be used to
  reference the query we just made.

5
Array handling in PHP

• In PHP, arrays are associative. Any number or
  string can be used to index an array.
• lt?
• array"hello" 3
• array5 "how are you?"
• while (list(column, value) each(array))
• print("column value\n")
• reset(array)
• ?gt
• This example would print
• hello 3
• 5 how are you?
• The command reset(array) puts the array iterator
  back to the beginning of the array.

6
Getting the results from a query

• After issuing a query, you retrieve the results
  using the variable result.
• lt?
• if (mysql_num_rows(result) 0)
• print("No results matching your
  queryltBRgt\n")
• else
• print("Here are the resultsltBRgt\n")
• while (row mysql_fetch_row(result))
• while (list(colname, value) each(row))
  
• print("value ")
• print("ltBRgt\n")
• ?gt

7
HTML forms and PHP variables

• From an HTML page that had this form
• ltFORM ACTION"target.php" METHOD"GET"gt
• ltINPUT TYPE"TEXT" NAME"myvar"gt
• ltINPUT TYPE"TEXT" NAME"yourvar"gt
• ltINPUT TYPE"SUBMIT" NAME"submit"gt
• lt/FORMgt
• The PHP script (target.php) will receive the
  variables from the form by the same name
• lt?
• print("you entered myvar _GETmyvar,
  yourvar _GETyourvar\n")
• ?gt

8
Useful string stuff in PHP

• Difference between single and double quotes
• lt?
• name "Joe"
• print("hello, your name is name\n")
• print(hello, your name is name\n)
• ?gt
• Output hello, your name is Joe
• hello, your name is name
• trimmed trim(" this string has whitespace ")
  removes leading and trailing whitespace
• encoded urlencode("this is a non-encoded url
  string") changes the argument so that it will be
  part of a valid URL