DB insert query not working. How to fix?

Question

PHP

INSERT query not working

spoiler

$cat = $_POST['cat'];
$title = $_POST['title'];
$keyw = $_POST['keywords'];
$descr = $_POST['description'];
$textt = $_POST['text'];
$hard = $_POST['hard'];
$mini_img = $_POST['mini_img'];
$source = $_POST['source'];
$file = $_POST['file'];
$file_size = $_POST['file_size'];
$demo = $_POST['demo'];
$syntax = $_POST['syntax'];
$view = 0;
$author = "Николай Чахов";

echo "<pre>";
var_dump ($_POST);
echo "</pre>";

$query = "INSERT INTO `post` (`post_id`, `cat`, `title`, `keywords`, `description`, `text`, `hard`, `mini_img`, `author`, `source`, `file`, `file_size`, `demo`, `date', `view`, `syntax`) 
VALUES (' ',$cat,$title,$keywords,$description,$text,$hard,$mini_img,$author,$source,$file,$file_size,$demo, NOW(),$view,$syntax)";

$result = $con->query($query);
if ($result == true){ 	
  echo "<p>Информация занесена в базу данных</p>"; 
} else { 	
    echo "<p>Информация не занесена в базу данных</p>"; 
    echo('Ошибка : ('. $con->connect_errno .') '. $con->connect_error);
}

The request fails and returns no errors.

Answer 1

No wonder it doesn't work. Everything is wrong here.

1. A space cannot be inserted into an auto-increment field. It is necessary to insert either null or skip this field altogether.
   
2. Variables should not be sent directly, but through substitutions
   
3. Errors should never be output manually, but you need to configure the database once so that it reports errors itself
   

Take the connection code from here
And execute the query itself like this:
All variables must be replaced in the query with question marks,
then prepare the query,
bind variables to it,
and execute

$query = "INSERT INTO `post` (`post_id`, `cat`, `title`, `keywords`, ...) 
VALUES (null,?,?,?, ..., NOW(),?,?)";
$stmt = $con->prepare($query);
$stmt->bind_param("sss...", $cat,$title,$keywords, ...);
$stmt->execute();
echo "<p>Информация занесена в базу данных</p>";

The number of question marks in the query and the number of "s"s in the first parameter of bind_param must match the number of variables.