help with php mysql query

[misheck]

I have a top navigation menu for my website which consist of news, sports, health etc. I need make one php page and query that will render the page main to the selected section/menu. Is it going to be safe to use value using $GET and assign the categories in the hyperlink <a href="content.php?category=sports" and then retrieve the category. I not sure if its safe to send any queries to your database from a $GET request so I am looking for a better alternative.

[NogDog]

As far as database SQL injection issues go, you should be OK as long as you filter the supplied value through the applicable escaping mechanism for the database interface being used (or use prepared statements if applicable). If you do that, the only other thing you need to do is make sure you gracefully handle situations where the value received in $_GET is not found by the DB query.

[misheck]

Thanks for the help I think this is the situation I have to use case or php switch statement and assign a default value just in case no data is found.

[NogDog]

A simple if/else would probably be sufficient:

$result = mysql_query($sql);
if($result)
{
   if(mysql_num_rows($result)
   {
      $row = mysql_fetch_assoc($result);
      echo $row['column_name'];
   }
   else
   {
      echo $default_stuff_goes_here;
   }
}
else
{
   // handle database error here
}