Okay today I'm going to show you how to make a simple banner rotator... You can use it for your ads on your site 
First of all we must create tables to database:
[highlight="SQL"]
CREATE TABLE `banner` (
`id` int(5) NOT NULL auto_increment,
`bannerimg` tinytext NOT NULL,
`bannerurl` varchar(100) NOT NULL,
`bannertxt` varchar(100) NOT NULL,
`views` int(5) NOT NULL default '0',
PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ;
[/highlight]
Now we must start with our script..
Code:
<?php
$SQLhost = "localhost";
$SQLuser = "";
$SQLpass = "";
$DB = "";
$SQLhost = "localhost"; - Here will be your SQL host, usually it's localhost but it can be something else also.. if you want to know what's your host.. contact with your hosting provider
$SQLuser = ""; - your database username
$SQLpass = ""; - your database password
$DB = ""; - Database
Code:
mysql_connect($SQLhost, $SQLuser, $SQLpass) or die("Can not connect to database: ".mysql_error());
mysql_select_db($DB) or die("Can not select database: ".mysql_error());
mysql_connect($SQLhost, $SQLuser, $SQLpass) or die("Can not connect to database: ".mysql_error()); - This will connect to the database and if it can not connect, then it will generate a error message with details why you can't connect to your database
mysql_select_db($DB) or die("Can not select database: ".mysql_error()); - It will select a database for you.. but if it can't select it will generate a detailed error 
Now let's find out how many banners we have in our database and let's generate a random number 
Code:
$query = mysql_query("SELECT * FROM banner");
$numTab = mysql_num_rows($query);
$RandNum = (rand()%$numTab);
$query = mysql_query("SELECT * FROM banner LIMIT $RandNum, 1");
$query = mysql_query("SELECT * FROM banner"); - It will select all tables from banner table
$numTab = mysql_num_rows($query); - This will show us how many records are in our table
Another 2 rows will generate a random number and they will select random banner.
Now let's show our banner.
Code:
while ($row = mysql_fetch_array($query)){
$banURL = $row['bannerurl'];
$banTXT = $row['bannertxt'];
$Banner = $row['bannerimg'];
$BanViews = $row['views'];
$BanID = $row['id'];
echo"<a href='".$banURL."' target='_blank' title='".$banTXT."'><img src='".$banner."' alt='".$banTXT."' border='0'></a>";
$newViews = $BanViews+1;
mysql_query("UPDATE banner SET views = $newViews WHERE id = $BanID");
}
while ($row = mysql_fetch_array($query)){ - Starts a while and get's info from the table
$banURL = $row['bannerurl']; - Banner's URL
$banTXT = $row['bannertxt']; - Banner's text
$Banner = $row['bannerimg']; - Banner itself
$BanViews = $row['views']; - Banner's views
$BanID = $row['id']; - Banner's ID
echo"<a href='".$banURL."' target='_blank' title='".$banTXT."'><img src='".$banner."' alt='".$banTXT."' border='0'></a>"; - Shows the banner that was randomly chosen from the table
$newViews = $BanViews+1; - Increases banner views by 1
mysql_query("UPDATE banner SET views = $newViews WHERE id = $BanID"); - Updates banner views
And we are done
Simple 'eh 
Okay here's the full script:
Code:
<?php
$SQLhost = "localhost";
$SQLuser = "";
$SQLpass = "";
$DB = "";
mysql_connect($SQLhost, $SQLuser, $SQLpass) or die("Can not connect to database: ".mysql_error());
mysql_select_db($DB) or die("Can not select database: ".mysql_error());
$query = mysql_query("SELECT * FROM banner");
$numTab = mysql_num_rows($query);
$RandNum = (rand()%$numTab);
$query = mysql_query("SELECT * FROM banner LIMIT $RandNum, 1");
while ($row = mysql_fetch_array($query)){
$banURL = $row['bannerurl'];
$banTXT = $row['bannertxt'];
$Banner = $row['bannerimg'];
$BanViews = $row['views'];
$BanID = $row['id'];
echo"<a href='".$banURL."' target='_blank' title='".$banTXT."'><img src='".$banner."' alt='".$banTXT."' border='0'></a>";
$newViews = $BanViews+1;
mysql_query("UPDATE banner SET views = $newViews WHERE id = $BanID");
}
?>
Enjoy
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