Question

I am trying to do a search across 29 fields in my database in my PHP project. I am using mysqli to connect to my database. My query works fine when I do not try to use bind_param(), but fails when I do with the error:

PHP Warning:  mysqli_stmt::bind_param() [<a href='mysqli-stmt.bind-param'>mysqli-stmt.bind-param</a>]: Number of variables doesn't match number of parameters in prepared statement in /search.php on line 6

My code is as follows:

<?php 
$find = $_POST['find'];
if (strcasecmp($_POST['in'], 'users') == 0) {

$query = $db->prepare("SELECT u.id, u.group_id, u.username, u.email, m.credits, m.first_name, m.last_name, m.address1, m.address2, m.city, m.state, m.country, m.zipcode, m.about, m.account_status, m.vacation_status FROM kf_users u JOIN kf_usermeta m ON u.id = m.id WHERE u.id LIKE  '%?%' OR u.group_id LIKE  '%?%' OR u.ip_address LIKE  '%?%' OR u.username  LIKE  '%?%' OR u.password LIKE  '%?%' OR u.salt LIKE  '%?%' OR u.email LIKE  '%?%' OR u.activation_code LIKE  '%?%' OR u.forgotten_password_code LIKE  '%?%' OR u.remember_code LIKE  '%?%' OR u.created_on LIKE  '%?%' OR u.last_login LIKE '%?%' OR u.active LIKE  '%?%' OR u.FUID LIKE  '%?%' OR m.id LIKE  '%?%' OR m.credits LIKE  '%?%' OR m.rating LIKE  '%?%' OR m.user_id LIKE  '%?%' OR m.first_name LIKE  '%?%' OR m.last_name LIKE  '%?%' OR m.address1 LIKE  '%?%' OR m.address2 LIKE  '%?%' OR m.city LIKE  '%?%' OR m.state LIKE  '%?%' OR m.country LIKE  '%?%' OR m.zipcode LIKE  '%?%' OR m.about LIKE  '%?%' OR m.account_status LIKE  '%?%' OR m.vacation_status LIKE '%?%'");
$query->bind_param('sssssssssssssssssssssssssssss',$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find,$find);
$query->execute();
$query->bind_result($id, $group, $username, $email, $credits, $first_name, $last_name, $address1, $address2, $city, $state, $country, $zipcode, $about, $account_status, $vacation_status);

while ($query->fetch()) {
    $result['id'] = $id;
    $result['group'] = $group;
    $result['username'] = $username;
    $result['email'] = $email;
    $result['credits'] = $credits;
    $result['first_name'] = $first_name;
    $result['last_name'] = $last_name;
    $result['address1'] = $address1;
    $result['address2'] = $address2;
    $result['city'] = $city;
    $result['state'] = $state;
    $result['country'] = $country;
    $result['zipcode'] = $zipcode;
    $result['about'] = $about;
    $result['account_status'] = $account_status;
    $result['vacation_status'] = $vacation_status; 
    $output[] = $result;
}

$query->close();

}
?>

Again, if I comment out my bind_param() line, and replace the ? in my query with my search term the data is returned, where as is I get an error and no data. Anyone have any ideas on what might be the issue here?

Answer 1

Binding parameters is not the same as string interpolation; you cannot just replace your variable with ?, nor should you quote them. The placeholder is for the entire value.

Instead, you should prepare your query like this

$query = $db->prepare('SELECT ... WHERE u.id LIKE ? OR u.group_id LIKE ? ... ');

Then wrap your value in the wildcard characters

$find = '%' . $find . '%';

Update

I would very strongly suggest using PDO instead of MySQLi. With it you can use named placeholders, for example

$stmt = $pdo->prepare('SELECT ... WHERE u.id LIKE :term OR u.group_id LIKE :term ... ');
$find = '%' . $find . '%';
$stmt->bindParam('term', $find);
$stmt->execute();

This way, you can reuse the same placeholder throughout your query