PHP绑定变量，无效的参数编号错误或PDO更新语句

Question

我使用PDO在PHP中构建了一条更新语句，但是始终出现此错误。

ERROR: SQLSTATE[HY093]: Invalid parameter number: number of bound variables does not match number of tokens

我数了数又重新数了（25），花了一段时间确认我的语法正确，并且我不明白自己在做什么错。

这是代码：

$sql = "UPDATE :tablename
        SET entryName = :entryname,
        entryAdd1 = : add1,
        entryAdd2 = :add2,
        entryCity = :city,
        entryCounty = :county,
        entryCountry = :country,
        entryPC = :postcode,
        entryPhone = :phone,
        entryEmail = :email,
        entryURL = :entryurl,
        entryDesc = :entryDesc,
        entryImg = :entryimg,
        entryStar  = :star,
        entryCuststar = :custstar,
        chains = :chains,
        cafe = :cafe,
        fishandchips = :fishandchips,
        indian = :indian,
        itallian = :italian,
        pizzeria = :pizzeria,
        tapas = :tapas,
        tearooms = :tearooms
        WHERE :colname = :entryid";

        $statement = $conn->prepare($sql);

        $statement->bindParam(":tablename", $tablename, PDO::PARAM_STR);

        $statement->bindParam(":entryname", $entryname, PDO::PARAM_STR);
        $statement->bindParam(":add1", $add1, PDO::PARAM_STR);
        $statement->bindParam(":add2", $add2, PDO::PARAM_STR);
        $statement->bindParam(":city", $entrytown, PDO::PARAM_STR);
        $statement->bindParam(":county", $entrycounty, PDO::PARAM_STR);
        $statement->bindParam(":country", $entrycountry, PDO::PARAM_STR);
        $statement->bindParam(":postcode", $entrypostcode, PDO::PARAM_STR);
        $statement->bindParam(":phone", $entryphone, PDO::PARAM_STR);
        $statement->bindParam(":email", $entryemail, PDO::PARAM_STR);
        $statement->bindParam(":entryurl", $entryurl, PDO::PARAM_STR);
        $statement->bindParam(":entryDesc", $entrydesc, PDO::PARAM_STR);
        $statement->bindParam(":entryimg", $entryicon, PDO::PARAM_STR);
        $statement->bindParam(":star", $star, PDO::PARAM_STR);
        $statement->bindParam(":custstar", $custstar, PDO::PARAM_STR);
        $statement->bindParam(":chains", $chains, PDO::PARAM_INT);
        $statement->bindParam(":cafe", $cafe, PDO::PARAM_INT);
        $statement->bindParam(":fishandchips", $fishchips, PDO::PARAM_INT);
        $statement->bindParam(":indian", $indian, PDO::PARAM_INT);
        $statement->bindParam(":italian", $italian, PDO::PARAM_INT);
        $statement->bindParam(":pizzeria", $pizzeria, PDO::PARAM_INT);
        $statement->bindParam(":tapas", $tapas, PDO::PARAM_INT);
        $statement->bindParam(":tearooms", $tearooms, PDO::PARAM_INT);

        $statement->bindParam(":colname", $colname, PDO::PARAM_STR);
        $statement->bindParam(":entryid", $entryid, PDO::PARAM_INT);

        $count = $statement->execute();

我进一步说明$ conn变量，这只是我正在创建的练习目录。 如果有人能指出正确的方向，我将不胜感激。

Answer 1

表名和列名不能用PDO中的参数替换。 您必须将其替换为实际名称，当然，您可以根据需要过滤掉不需要的数据，而不必使用准备好的语句。

无法运作：

$sth = $dbh->prepare('SELECT name, colour, calories FROM ?  WHERE calories < ?');

这项工作！

$sth = $dbh->prepare('SELECT name, colour, calories FROM fruit WHERE calories < ?');

Answer 2

您无法参数化表/列的名称。 如果您需要它们是动态的，请尝试以下方法：

$sql = "UPDATE " . $tablename . "
    SET entryName   = :entryname,
    entryAdd1       = :add1,
    entryAdd2       = :add2,
    entryCity       = :city,
    entryCounty     = :county,
    entryCountry    = :country,
    entryPC         = :postcode,
    entryPhone      = :phone,
    entryEmail      = :email,
    entryURL        = :entryurl,
    entryDesc       = :entryDesc,
    entryImg        = :entryimg,
    entryStar       = :star,
    entryCuststar   = :custstar,
    chains          = :chains,
    cafe            = :cafe,
    fishandchips    = :fishandchips,
    indian          = :indian,
    itallian        = :italian,
    pizzeria        = :pizzeria,
    tapas           = :tapas,
    tearooms        = :tearooms
    WHERE " . $colname . " = :entryid";

    $statement = $conn->prepare($sql);

    $statement->bindParam(":entryname", $entryname, PDO::PARAM_STR);
    $statement->bindParam(":add1", $add1, PDO::PARAM_STR);
    $statement->bindParam(":add2", $add2, PDO::PARAM_STR);
    $statement->bindParam(":city", $entrytown, PDO::PARAM_STR);
    $statement->bindParam(":county", $entrycounty, PDO::PARAM_STR);
    $statement->bindParam(":country", $entrycountry, PDO::PARAM_STR);
    $statement->bindParam(":postcode", $entrypostcode, PDO::PARAM_STR);
    $statement->bindParam(":phone", $entryphone, PDO::PARAM_STR);
    $statement->bindParam(":email", $entryemail, PDO::PARAM_STR);
    $statement->bindParam(":entryurl", $entryurl, PDO::PARAM_STR);
    $statement->bindParam(":entryDesc", $entrydesc, PDO::PARAM_STR);
    $statement->bindParam(":entryimg", $entryicon, PDO::PARAM_STR);
    $statement->bindParam(":star", $star, PDO::PARAM_STR);
    $statement->bindParam(":custstar", $custstar, PDO::PARAM_STR);
    $statement->bindParam(":chains", $chains, PDO::PARAM_INT);
    $statement->bindParam(":cafe", $cafe, PDO::PARAM_INT);
    $statement->bindParam(":fishandchips", $fishchips, PDO::PARAM_INT);
    $statement->bindParam(":indian", $indian, PDO::PARAM_INT);
    $statement->bindParam(":italian", $italian, PDO::PARAM_INT);
    $statement->bindParam(":pizzeria", $pizzeria, PDO::PARAM_INT);
    $statement->bindParam(":tapas", $tapas, PDO::PARAM_INT);
    $statement->bindParam(":tearooms", $tearooms, PDO::PARAM_INT);

    $statement->bindParam(":entryid", $entryid, PDO::PARAM_INT);

    $count = $statement->execute();

谢谢，

安德鲁