Sort DESC then ASC

[jason97673]

So I am sure you know how when you click a header on a column of data it sorts from largest to smallest? Then you want to click the column header again and sort the opposite direction, smallest to largest.

 

I am using MySQL obviously, and currenly I have my data sorted from largest numbers to smallest. However if you click the column header again, I want it to sort the opposite direction.

 

Here is the code I have that sorts DESC

 

$page_name="1st_downs.php"; //  If you use this code with a different page ( or file ) name then change this 

@$column_name=$_GET['column_name']; // Read the column name from query string. 


$start=$_GET['start'];								// To take care global variable if OFF
if(!($start > 0)) {                         // This variable is set to zero for the first page
$start = 0;
}

$eu = ($start - 0); 
$limit = 100;                                 // No of records to be shown per page.
$this1 = $eu + $limit; 
$back = $eu - $limit; 
$next = $eu + $limit; 


/////////////// WE have to find out the number of records in our table. We will use this to break the pages///////
$query2=" SELECT * FROM 1st  ";
$result2=mysql_query($query2);
echo mysql_error();
$nume=mysql_num_rows($result2);
/////// The variable nume above will store the total number of records in the table////

/////////// Now let us print the table headers ////////////////
echo '<div id="main" class="text">';

echo '<table>';
echo 	"<tr>";
echo 	"<td><a href='$page_name?column_name=quarterback'>Quarterback</a></td>";
echo 	"<td><a href='$page_name?column_name=completions'>Completions</a></td>";
echo 	"<td><a href='$page_name?column_name=attempts'>Attempts</a></td>";
echo 	"<td><a href='$page_name?column_name=comp_percent'>Comp%</a></td>";
echo 	"<td><a href='$page_name?column_name=yards'>Yards</a></td>";
echo 	"<td><a href='$page_name?column_name=ypa'>YPA</a></td>";
echo 	"<td><a href='$page_name?column_name=touchdowns'>Touchdowns</a></td>";
echo 	"<td><a href='$page_name?column_name=td_percent'>TD%</a></td>";
echo 	"<td><a href='$page_name?column_name=interceptions'>Interceptions</a></td>";
echo 	"<td><a href='$page_name?column_name=int_percent'>INT%</a></td>";
echo 	"<td><a href='$page_name?column_name=rating'>rating</a></td>";
echo	"</tr>";

////////////// Now let us start executing the query with variables $eu and $limit  set at the top of the page///////////
$query=" SELECT * FROM 1st";

if(isset($column_name) and strlen($column_name)>0){
$query = $query . " order by $column_name";
}

$data=mysql_query($query);
echo mysql_error();

//////////////// Now we will display the returned records in side the rows of the table/////////
while($row = mysql_fetch_array($data))
{
echo '<tr><td>' .$row['quarterback'] .'</td>';
echo '<td>' .$row['completions'] .'</td>';
echo '<td>' .$row['attempts'] .'</td>';
echo '<td>' .$row['comp_percent'] .'%</td>';
echo '<td>' .$row['yards'] .'</td>';
echo '<td>' .$row['ypa'] .'</td>';
echo '<td>' .$row['touchdowns'] .'</td>';
echo '<td>' .$row['td_percent'] .'%</td>';
echo '<td>' .$row['interceptions'] .'</td>';
echo '<td>' .$row['int_percent'] .'%</td>';
echo '<td>' .$row['rating'] .'</td></tr>';
}
echo "</table>";

 

Thanks for any help..

[trq]

Its quite simple. You need to make your sort link rotate between desc and asc and pass this back to your query. eg;

 

<?php

  if (isset($_GET['sort'])) {
    $sql = "SELECT * FROM foo ORDER BY " . strtoupper(mysql_real_escape_string($_GET['sort']));
    if ($_GET['sort'] == 'desc') {
      $sort = 'asc';
    } else {
      $sort = 'desc';
    }
  } else {
    $sql = "SELECT * FROM foo ORDER BY DESC";
  }

  // execute your query.

  // display link.
  echo "<a href='?sort=$sort'>$sort</a>";

?>

[jason97673]

Thanks, I will try implement this into my code