我有一个搜索，当用户键入关键字时，脚本会在数据库中查找该关键字：

<form method="GET">
    <input type="text" name="q" id="keyword" placeholder="Enter a keyword" > 
    <input type="submit" value="Search" >
</form>

提交表格后，我检查以下内容：

//Check is the form is submitted.
if( isset($_GET['q']) ){

    //Assign the submitted keyword to a variable.
    $query = $_GET['q'];

    //Check if the keyword is empty.
    if(!empty($query)){

        //Check if the keyword matches the pattern.
        //The pattern checks that the keyword contains characters from any language and maybe there are spaces between them.
        $pattern = "~^\p{L}[\p{L}\p{M}\h()]*$~u";

        //If the keyword matches the pattern.
        if(preg_match($pattern, $query)){

            //Fetch data from the Database.
            $stmt = $conn->prepare('SELECT * FROM posts WHERE title OR description LIKE  :s LIMIT 5');
            $stmt->bindValue(':s', '%' . $query . '%', PDO::PARAM_STR);
            $stmt->execute();
            $posts = $stmt->fetchAll();

        }
    }

这些检查是否足以阻止sql注入和其他攻击？
或者我需要建立一个黑名单？或者检查其他东西？