PHP - MySQL Connection8 March 2006

Adina Crainiceanu

www.cs.usna.edu/~adina

IT420: Database Management and Organization

Web Database Architecture

Client browserWeb server with PHP enabled

Database Management System

HTTP API

Goals Today

Connect from PHP to MySQL

MySQL

Relational Database Management System Free Open source Portable High performance Support available

Example Application

Database: dbmusicTable: songs(ISBN, Title, SingerID, Length)

Use DBMS from PHP

Connect to the database server Specify database to use Send queries and retrieve results Process results Close connection

All PHP functions return ‘false‘ if operation unsuccessful!

Example: $searchterm = $_POST['searchterm'];//connect@ $db = mysql_connect('localhost','root');if (!$db){

echo('connect failed');exit;

}$dbselected= mysql_select_db('dbmusic') or exit('could not select db');//query$query = "select * from songs where Title like '%$searchterm%'";//process results$results = mysql_query($query) or die("could not retrieve rows");while ($row = mysql_fetch_row($results)){

echo 'Title: '.$row[1].' <br>';}//close connectionmysql_free_result($results);mysql_close($db);

Connect to MySQL

dbconnection mysql_connect(servername, username, [password])

Always test and handle errors! Example:

$dbconn = mysql_connect(‘localhost’,’root’);if (!$dbconn){

echo ‘Could not connect to db. Exit’;exit;

}

Select Database to Use

bool mysql_db_select(dbname, [dbconnection])

Always test and handle errors! Example:

$dbs = mysql_db_select(‘dbmusic’) ordie(‘Could not select db’);

Query the Database

qresult mysql_query(query) Example:

$query = “select * from songs where Title like ‘%home%’ ”;

$results = mysql_query($query);

Process Select Results

nbrows = mysql_num_rows(qresult) row = mysql_fetch_row(qresult) row = mysql_fetch_array(qresult) Example:

while ($row = mysql_fetch_row($results)){

foreach($row as $column) echo “$column ”;

echo “<br />”;

}

Check Modification Results

intvar = mysql_affected_rows() Used after INSERT, DELETE, UPDATE

Disconnect from Database

Free query results mysql_free_result(qresult);

Close connection mysql_close(connection)

VP-5 MVR Fund Raiser Application

Lab Exercise

Recover the database vp5fund created last time D:\sokkit\mysql\data

Start MySQL Monitor D: cd sokkit\mysql\bin mysql –u root

To use the database: use vp5fund; These tables should exist:

Items(ItemName, Price) Orders(OrderID, ShippingAddress) ItemsOrdered(OrderID, ItemName, Quantity)

Insert few rows in tables

Lab Exercise: PHP + MySQL

Display all orders from VP-5 Fund Raiser application. For each order display: OrderID Shipping address Items names and price

Display all orders from VP-5 Fund Raiser application with shipping address in Maryland.

Lab Exercise: PHP + MySQL

Save order data from VP-5 Fund Raiser application into vp5fund database.

Save Your Work!

Copy the D:\sokkit\mysql\data\ directory to your X drive