Trying to avoid duplicate results

[Stieny]

The code listed below works with no errors, but I want to avoid the user from finding duplicate locations. How would I go about doing that?

 

<?PHP

require_once('auth.php'); 
include("gm_cnst.php"); 

//Set the chance to find another player
$chance = (($user[scouts]*$bonus[scouts]) + ($user[scouts]*$bonus[explore])) * rand(0,5);


//Set number of users in db
$qry="SELECT member_id FROM members";
$result = mysql_query($qry);
$count = 0;	
while(mysql_fetch_array($result)) 
{
$count++;
}   	

//Make sure the user has enough turns
      if($user[turns] <= 0)
   {
            header('refresh: 4; url= exploration.php');
            echo $error_header;
            echo "You do not have enough turns to do that.";
            echo $footer;
            exit();
   }

//Search for other players
      	if($chance <=0 and $chance < 999)
   	{
        header('refresh: 4; url= exploration.php');
        echo $error_header;
        echo "Your Scouts searched the lands, but only came back tired and hungry.";
        echo $footer;
        exit();
   	}      

		elseif($chance > 1000 and $chance < 4999)
	{
		$leader = rand(1,$count);
		$qry="SELECT * FROM members WHERE member_id='".$leader."'";
		$result = mysql_query($qry);
		$loc = mysql_fetch_array($result);
		echo "You have found the borders of ";
		echo $loc['kingdom']; 
		echo "<br>where "; 
		echo $loc['leader']; 
		echo " resides.<p>";
		echo $footer;
		mysql_query("INSERT INTO member_locations (leader, found) VALUES ($user[member_id],$leader)");
		exit();
	}

		elseif($chance > 5000 and $chance < 9999)
	{
		header('refresh: 4; url= exploration.php');
		echo $success_header;

			for ( $c = 1; $c <= 2; $c++) 
		{
			$leader = rand(1,$count);
			$qry="SELECT * FROM members WHERE member_id='".$leader."'";
			$result = mysql_query($qry);
			$loc = mysql_fetch_array($result);
			echo "You have found the borders of ";
			echo $loc['kingdom']; 
			echo "<br>where "; 
			echo $loc['leader']; 
			echo " resides.<p>";
			print_r($opp_leader);
			echo $footer;
			mysql_query("INSERT INTO member_locations (leader, found) VALUES ($user[member_id],$leader)");
			exit();
		}
	}
?>

[premiso]

You can use sessions to store an array of locations recently found and do a loop to check that array and if the location was found find a new one. If you want this to last longer than the session, permanently, I would suggest creating a new table in your database, "locations_found", which will list a memberid and locationid of the locations that a member has already found. Then you would just check against that to see if the locations has already been discovered by a user.

 

Hope that makes sense, good luck!

[Stieny]

Well, I made a new table called member_locations that shows who finds what. The problem I am having is first retrieving this data to compare the results (as it is on numerous rows), and second, incorporating it into the code I have so far. The nestings are getting a little confusing to me. Currently members_location is set up like:

 

| leader | | found|

|    1      | |    2  |

|    1      | |    3  |

 

How do you fetch results from multiple rows?

 

I know that I would want to do something like IF $leader = found chose again, but it is getting the found I am having troubles with.

[premiso]

You can fetch the results of multiple rows via:

 

$sql = "SELECT found FROM locations_members WHERE leader = some_condition";
$query = mysql_query($sql) or trigger_error("Query Failed " . mysql_error());

$found = false;
while ($row = mysql_fetch_assoc($query)) {
      if ($row['found'] == $new_location) {
             echo 'Location already found.';
             $found = true;
             break;
     }
}

if (!$found) {
     // insert into memberlocations
}else {
    // do something that you want to do
}

 

That is what you are looking for I believe.

[Stieny]

ahhhh finally getting somewhere!!!

[premiso]

Well looking at the code I wrote I think this might be better suited for you:

 

$sql = "SELECT found FROM locations_members WHERE leader = some_condition";
$query = mysql_query($sql) or trigger_error("Query Failed " . mysql_error());

if (mysql_num_rows($query) > 0) {
    $locations = array();
    while ($row = mysql_fetch_assoc($query)) {
         $locations[] = $row['found'];
    }

   while (in_array($new_location, $locations)) {
          $new_location = "some random location";
   }
}

// insert the $new_location variable to the DB here

 

I was just bored and saw that the above would probably suit your needs better.

 

EDIT:

The one thing you will have to watch out for is if they have discovered everything then this will be an infinite loop, so yea.

[Stieny]

first solution worked perfect... thanks very much