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PHP

Posted by johncashin
johncashin
4,979 Points

INSERT & SELECT to see if entry exists

Hi

I'm having a little trouble wrapping my head around this. I want to check the table on submit to see if the email already exists. The issue I have is I make the entry but I don't think my query on the email column is working or i'm not binding to stmt correctly.

Any help would be greatly appreciated. 

<?php
$date = new DateTime();

//VARIABLES & INSERT QUERY
if (isset($_POST["submit"])) {

    // Get the form fields and remove whitespace.
    $name   = strip_tags(trim($_POST["name"]));
    $name   = str_replace(array("\r", "\n"), array(" ", " "), $name);
    $mobile = strip_tags(trim($_POST["mobile"]));
    $mobile = str_replace(array("\r", "\n"), array(" ", " "), $mobile);
    $date = strip_tags(trim($_POST["date"]));
    $date = str_replace(array("\r", "\n"), array(" ", " "), $date);
    $email  = filter_var(trim($_POST["email"]), FILTER_SANITIZE_EMAIL);
    $userID = mysqli_insert_id($success);

    //INSERT INTO DATABASE

    if ($stmt = $success->prepare(
        "INSERT INTO dbtest (name, email, mobile, date) VALUES (?, ?, ?, ?);
           SELECT email FROM dbtest WHERE email=?"
    )) {

        $stmt->bind_param("ssss", $name, $email, $mobile, $date);

        if ($stmt->execute()) {
            $stmt->store_result();

            $email_check = "";
            $stmt->bind_result($email_check);
            $stmt->fetch();

            if ($stmt->num_rows == 1) {

                echo "That Email already exists.";
                exit;

            } else {

                header('Location: success.php');
                exit();

                $stmt->close();
                $success->close();
            }
        }
    }
}

1 Answer

Andrew Shook
Andrew Shook
31,709 Points
Andrew Shook
Andrew Shook
31,709 Points

I would make a separate query to determine whether or not the email exists in the DB before doing the insert query.

<?php 
if (isset($_POST["submit"])) {

    // Get the form fields and remove whitespace.
    $name   = strip_tags(trim($_POST["name"]));
    $name   = str_replace(array("\r", "\n"), array(" ", " "), $name);
    $mobile = strip_tags(trim($_POST["mobile"]));
    $mobile = str_replace(array("\r", "\n"), array(" ", " "), $mobile);
    $date = strip_tags(trim($_POST["date"]));
    $date = str_replace(array("\r", "\n"), array(" ", " "), $date);
    $email  = filter_var(trim($_POST["email"]), FILTER_SANITIZE_EMAIL);
    $userID = mysqli_insert_id($success);

    //Question: is the name of your table dbtest or is that the name of your DB?
    if($smt = $success->prepare( "SELECT email FROM dbtest WHERE email=?") && $stmt->execute() ){

         if ($stmt->num_rows  == 0) {
                //no rows in the dd means the email is not used so we insert the data into the data base.
               if ($stmt = $success->prepare("INSERT INTO dbtest (name, email, mobile, date) VALUES (?, ?, ?, ?);")) {
                    // code for inserting and binding then redirect and exit
               }else{
                   //prepare failed.
               }
        }

    }else{
            //prepare failed.
        }

    //if we make this far in the code then we know that the that the email has been take. 
    header('Location: success.php');
    exit();