[SOLVED] Query Issue

[ainoy31]

Hello.  I have a mailing list site where my client can create a new mailing list.  The problem is where I am trying to check to make sure that there is no duplicate mailing list entry.  Here is my code:

 

switch($_POST['action'])

{

case 'Add New Mailing List':

 

if(!mysql_query("SELECT * FROM ml_lists WHERE listname = " . $_POST['listname']));

{

$sql = "INSERT INTO ml_lists (`listname`) VALUES ('" . $_POST['listname'] . "')";

mysql_query($sql) or die('Could not add mailing list . ' . mysql_error());

echo "The mailing list for the " . $_POST['listname'] . " store has been created!";

}

else

{

echo "The mailing list for the " . $_POST['listname'] . " store already exists.  Please try again.";

}

break;

 

I just get a blank white screen.  ty

[Illusion]

better to have a UNIQUE key on listname column.

[ainoy31]

Figured it out with the following:

 

$query = "SELECT * FROM ml_lists WHERE listname = '$list'";

$result = mysql_query($query) or die("Error: " . mysql_error());

$num = mysql_num_rows($result);

 

if($num == 0)

{

$sql = "INSERT INTO ml_lists (`listname`) VALUES ('$list')";

mysql_query($sql) or die('Could not add mailing list . ' . mysql_error());

echo "The mailing list for the " . $list . " store has been created!";

 

}

else

{

echo "The mailing list for the " . $list . " store already exists.  Please try again.";

}