PHP Structure

[bitcycle]

I have a database of music artist. I want the main page to show all artist. Then artist by genre with mainpage.php?cat=Rock and artists all artists alphabatized by letter like mainpage.php?letter=R. The mainpage show every artist in the database, mainpage.php?=Rock shows artists in a category and mainpage.php?=letter show all artists starting with the same letter. I created a letter field in the database. I understand how to structure the first if statement (if mainpage.php?cat=rock print all all rock artists but im not sure how to combine two conditions. like if mainpage.php?letter=a print all artists that start with a and only those and not all everty artist with it. Do I need a if elsif statement?Thanks Here is what I have so far

mark



[code]$db = mysql_connect("localhost", "root", "miy5uxiv");
mysql_select_db("db1",$db);
#$result = mysql_query("SELECT * FROM db1 ORDER BY letter",$db);
#$result2 = mysql_query("Select artist FROM db1 where cat='$cat'",$db) or die(mysql_error());
#$myrow2 = mysql_fetch_array($result2);

// start where condition with void
    $where = '' ;
    // verify if cat is set
    if ( $_REQUEST['cat'] != '' )
    {
        // set where condition
        $where = ' where cat = "'. $_REQUEST['cat'] .'" ORDER BY artist ' ;
    }
    // mount the sql string
    $sql = ' SELECT * FROM db1 '. $where  ;
    // execute the query
    $result = mysql_query ( $sql , $db );

while ($myrow = mysql_fetch_array($result))
{
echo "<TR><TD>";
  echo "<TD><a href=\"forumcode.php?id=".$myrow[id]."\">$myrow[artist]</a></br>";
echo "</br>";
}

echo "</TABLE>";

$wheretest = '';
if ($_REQUEST['letter'] != '')
{
        $wheretest = ' where letter = "'.$_REQUEST['letter'] .'" ';
  }

$sqltest = ' SELECT * FROM db1 '. $wheretest ;
$resulttest = mysql_query ($sqltest , $db );

$myrow2 = mysql_fetch_array($resulttest);
echo "<TR><TD>";
echo "<TD> $myrow2[artist]";
echo "</table>"
[/code]