Inserting a Value into SQL where the value doesnt already exist

[bicky]

Hello All

 

Hoping for some help this time

 

I have created a statement that works fine now, taking the value from a form and inserting into a MS SQL table.

 

I now want to expand the code, to only insert when the value doesnt already exist...

 

My Current Code is as follows:

 

$tsql = "INSERT INTO email_supp
        (email,date,source)
        VALUES
        (?,?,?)";

$today = date("d/m/y");
$source= 'Email Form';
$email = array($_POST['emailopt'], $today,$source);

/* Prepare and execute the query. */
$stmt = sqlsrv_query( $conn, $tsql, $email);
if( $stmt )
{
     echo "Row successfully inserted.\n";
}
else
{
     echo "Row insertion failed.\n";
     die( print_r( sqlsrv_errors(), true));
}

/* Free statement and connection resources. */
/*sqlsrv_free_stmt( $stmt);*/

sqlsrv_close( $conn);
?>

 

My main problem here is I dont really know how the value is taken from the form, I know its within this part (array($_POST['emailopt']) but If i wanted to just specify the value to a variable my PHP seems to then fall over.

 

ANY help would be appreciated..

 

Thanks in advance

 

Bicky

[AMcHarg]

Why not just add a constraint to the particular field on the database that you want to be unique?  This way your code will not actually be able add any duplicate entries, even if it tries to. 

[Pikachu2000]

You'll ned to clarify the question. Are you wanting to prevent duplicate entries, or what? Be as specific as possible as to what you need the script to do.