SQLSTATE: Invalid number of arguments: The number of bind variables does not match the number of tokens, line 102

Question

I received the SQLSTATE[HY093] error: The number of bind variables does not match the number of tokens, below line 102 of comments.php:

<?php

/*** Class for processing articles*/

class Comment
{
  // Attributes

  /*** @var int article ID in database*/
  public $id = null;

  /*** @var int The date the article will/has been published*/
  public $publicationDate = null;

  /*** @var string The full title of the article*/
  public $title = null;

  /*** @var string HTML content of the article*/
  public $content = null;

    /*** @var int article ID in database*/
    public $articleid = null;


  /*** Set the object's properties using the values ​​in the provided array
  *
  * @param assoc attribute value*/

  public function __construct( $data=array() ) {
    if ( isset( $data['id'] ) ) $this->id = (int) $data['id'];
    if ( isset( $data['publicationDate'] ) ) $this->publicationDate = (int) $data['publicationDate'];
    if ( isset( $data['title'] ) ) $this->title = preg_replace ( "/[^.,-_'"@?!:$ a-zA-Z0-9()]/", "", $data['title'] );
    if ( isset( $data['content'] ) ) $this->content = $data['content'];
      if ( isset( $data['articleid'] ) ) $this->articleid = (int) $data['articleid'];
  }


  /*** Set the properties of the object using the POST value of the edit form
  *
  * @param assoc form POST value*/

  public function storeFormValues( $params ) {

    // store all parameters
    $this->__construct( $params );

    // Parse and store the release date
    if ( isset($params['publicationDate']) ) {
      $publicationDate = explode ( '-', $params['publicationDate'] );

      if ( count($publicationDate) == 3 ) {
        list ( $y, $m, $d ) = $publicationDate;
        $this->publicationDate = mktime (0, 0, 0, $m, $d, $y);
      }
    }
  }


  public static function getById( $id ) {
    $conn = new PDO( DB_DSN, DB_USERNAME, DB_PASSWORD );
    $sql = "SELECT *, UNIX_TIMESTAMP(publicationDate) AS publicationDate FROM comments WHERE id = :id";
    $st = $conn->prepare( $sql );
    $st->bindValue( ":id", $id, PDO::PARAM_INT );
    $st->execute();
    $row = $st->fetch();
    $conn = null;
    if ( $row ) return new Comment( $row );
  }/*** Return all (or a certain range of) article objects in the database
  *
  * @param int optional Number of rows to return (default is all)
  * @param string optional column according to which articles are sorted (default is "publicationDate DESC")
  * @return Array|false An array containing two elements: results => array, a list of article objects; totalRows => total number of articles*/

    public static function getList( $art=1, $order="publicationDate DESC", $numRows=10000 ) {
    $conn = new PDO( DB_DSN, DB_USERNAME, DB_PASSWORD );
    $sql = "SELECT SQL_CALC_FOUND_ROWS *, UNIX_TIMESTAMP(publicationDate) AS publicationDate FROM comments WHERE articleid = :art 
        ORDER BY " . mysql_escape_string($order) . " LIMIT :numRows";

    $st = $conn->prepare( $sql );
    $st->bindValue( ":art", $art, PDO::PARAM_INT );
    $st->execute();
    $list = array();

    while ( $row = $st->fetch() ) {
      $comments = new Comment( $row );
      $list[] = $comment;
    }
  }


  /*** Insert the current article object into the database and set its ID attribute.*/

  public function insert() {

    // 插入文章
    $conn = new PDO( DB_DSN, DB_USERNAME, DB_PASSWORD );
    $sql = "INSERT INTO comments ( publicationDate, title, content, articledid ) VALUES ( FROM_UNIXTIME(:publicationDate), :title, :content, :articleid )";
    $st = $conn->prepare ( $sql );
    $st->bindValue( ":publicationDate", $this->publicationDate, PDO::PARAM_INT );
    $st->bindValue( ":title", $this->title, PDO::PARAM_STR );
    $st->bindValue( ":content", $this->content, PDO::PARAM_STR );
    $st->bindValue( ":articleid", $this->articleid, PDO::PARAM_STR );
    $st->execute();
    $this->id = $conn->lastInsertId();
    $conn = null;
  }


  /**
  * 在数据库中更新当前的文章对象。*/

  public function update() {

    // 更新文章
    $conn = new PDO( DB_DSN, DB_USERNAME, DB_PASSWORD );
    $sql = "UPDATE comments SET publicationDate=FROM_UNIXTIME(:publicationDate), title=:title, summary=:summary, content=:content, articleid=:articleid,imageExtension=:imageExtension WHERE id = :id";
    $st = $conn->prepare ( $sql );
    $st->bindValue( ":publicationDate", $this->publicationDate, PDO::PARAM_INT );
    $st->bindValue( ":title", $this->title, PDO::PARAM_STR );
    $st->bindValue( ":content", $this->content, PDO::PARAM_STR );
      $st->bindValue( ":articleid", $this->articleid, PDO::PARAM_STR );
    $st->bindValue( ":id", $this->id, PDO::PARAM_INT );
    $st->execute();
    $conn = null;
  }


  /*** Delete the current article object from the database.*/

  public function delete() {


    // 删除文章
    $conn = new PDO( DB_DSN, DB_USERNAME, DB_PASSWORD );
    $st = $conn->prepare ( "DELETE FROM comments WHERE id = :id LIMIT 1" );
    $st->bindValue( ":id", $this->id, PDO::PARAM_INT );
    $st->execute();
    $conn = null;
  }

}

?>

Answer 1

You are not binding all bindings here

$sql = "UNIX_TIMESTAMP(publicationDate) AS publicationDate
        FROM comments WHERE articleid = :art 
        ORDER BY some LIMIT :numRows";

$st = $conn->prepare( $sql );
$st->bindValue( ":art", $art, PDO::PARAM_INT );

You declare a binding called :numRows, but you don't actually bind anything to it.