Question

I currently am using mysql and php to display 9 random results from my table of about 1100 records.

Would it be possible to have a next and previous button even though it’s random? I looked at a couple of the examples already posted here but they seem to be application/project specific. Here is what my code looks like..

    function executeQuery($searchKey)
    {

        if ($searchKey == null)
        {
    $query = "SELECT DISTINCT flightNumber, flightCity FROM allFlights LIMIT 0,9";
        //DEBUG -echo "<p>$searchKey</p>";echo "<p>$query</p>";
        }
        else
        {
        //DEBUG -echo "<p>$searchKey</p>";echo "<p>var not null</p>";
           $query = "Select distinct * from allFlights where flightCity LIKE '%$searchKey%' LIMIT 0,9";
        //DEBUG -echo "<p>$searchKey</p>";echo "<p>$query</p>";
        }
   $result=mysql_query($query);
   $numrow=mysql_numrows($result);
   if ($numrow === 0)
   {
    $query = "Select distinct * from allFlights where flightNumber LIKE '%$searchKey%' LIMIT 0,9";
    $result=mysql_query($query);
    $numrow=mysql_numrows($result);
   }
return $result;
     }

       function populate ()
       {
         $searchKey = mysql_real_escape_string($_POST["search"]); //assigns user input to searchKey variable
         //DEBUG -echo "<p>$searchKey</p>";
         $result=executeQuery($searchKey);
         $numrow=mysql_numrows($result);

     if ($numrow == 0)
     {
        echo "<center><p><b> No results found, please try another keyword.</p></center></b>";
     }
     else
     { display results. -- this part i have working.
             }

I prefer upon loading the page this happens:
-The current position with respect to the # of flights available are listed. (Now showing 9 of 1100 flights)
-9 random flights are displayed.
-Next button that will show the next 9 flights (random would be nice.)
-Previous button that will show the previous(original) 9 flights (random would be nice.)

When all is said and done I would like to be able to load the page identify the 9 random flights, press next identify the new 9 random flights, then previous and identify the original 9 random flights.

Any help is much appreciated.

Answer 1

You can use ORDER BY RAND(seed) to give a pseudorandom order that is repeatable:

SELECT * 
FROM ....
ORDER BY RAND(9325)
LIMIT 99, 9

Adjust the offset to move back and forwards through the results. The seed can be any integer, and you can change it if you want to re-randomize the order, but you must use the same seed when pressing back or forward.