使用命名占位符时PHP / SQL插入错误

我有以下PHP PDO语句：

$STH = $this->_db->prepare("INSERT INTO UserDetails (FirstName, LastName, 
            Address, City, County, PostCode, Phone, Mobile, Sex, dob, 
            Fundraisingaim, Weeksaim, Lengthsaim, HearaboutID,
            MotivationID, WelcomePackID, ContactPrefID, TitleID) 
            VALUES
            (:firstName, :lastName, :address, :city, :county, :postCode, 
            :phone, :mobile, :sex, :dob, :fundraisingaim, :weeksaim,
            :lengthsaim, :hearabout, :motivation,
            :welcomePackPref, :contactPref, :title)");

$STH->execute($userData);

其中$userData是一个关联数组.我仔细检查了名称,我不明白为什么我收到以下错误：

sqlSTATE [HY093]：参数号无效：绑定变量数与令牌数不匹配

我犯了什么愚蠢的错误？

解决方法:

您的$userData必须具有与您的语句绑定的完全相同的占位符,不多也不少.请参阅PDOStatement::execute documentation,该部分显示“您无法绑定多于指定值的值”.

你需要准备你的参数execute()来准确匹配你的绑定.如果正确排列数组,使用array_intersect_key()很容易.我通常将它包装在一个函数中,它也会处理前缀,如下所示：

// Adds a prefix to a name for a named bind placeholder
function prefix($name) {
    return ':'.$name;
}

// like 'prefix()', but for array keys
function prefix_keys($assoc) {
    // prefix STRING keys
    // Numeric keys not included
    $newassoc = array();
    foreach ($assoc as $k=>$v) {
        if (is_string($k)) {
            $newassoc[prefix($k)] = $v;
        }
    }
    return $newassoc;
}

// given a map of datakeyname=>columnname, and a table name, returns an
// sql insert string with named bind placeholder parameters.
function makeInsertStmt($tablename, $namemap) {
    $binds = array_map('prefix', array_keys($namemap));
    return 'INSERT INTO '.$tablename.' ('.implode(',',$namemap).') VALUES ('
    .implode(',',$binds).')';
}

// returns an array formatted for an `execute()`
function makeBindData($data, $namemap) {
    // $data assoc array, $namemap name->column mapping
    return prefix_keys(array_intersect_key($data, $namemap));
}

// example to demonstrate how these pieces fit together
function RunTestInsert(PDO $pdo, $userData) {
    $tablename = 'UserDetails';
    // map "key in $userData" => "column name"
    // do not include ':' prefix in $userData
    $namemap = array(
      'firstName'       => "FirstName",
      'lastName'        => "LastName",
      'address'         => "Address",
      'city'            => "City",
      'county'          => "County",
      'postCode'        => "PostCode",
      'phone'           => "Phone",
      'mobile'          => "Mobile",
      'sex'             => "Sex",
      'dob'             => "dob",
      'fundraisingaim'  => "Fundraisingaim",
      'weeksaim'        => "Weeksaim",
      'lengthsaim'      => "Lengthsaim",
      'hearabout'       => "HearaboutID",
      'motivation'      => "MotivationID",
      'welcomePackPref' => "WelcomePackID",
      'contactPref'     => "ContactPrefID",
      'title'           => "TitleID",
    );
    $sql = makeInsertStmt($tablename, $namemap);
    $binddata = makeBindData($userData, $namemap);

    $pstmt = $pdo->prepare($sql);
    $pstmt->execute($binddata);
}

像这样的抽象的好处是你不需要担心绑定参数本身.