php - 如何执行动态 php、PDO 准备语句更新？

Question

我很难找到有关 pdo 更新准备语句的良好文档，更难以找到有关使用 pdo 准备语句动态更新数据库的文档。我的动态插入已经可以工作，但更新时遇到问题。我收到的错误是:

Warning: PDOStatement::execute() [pdostatement.execute]: SQLSTATE[HY093]: Invalid parameter number: parameter was not defined in /Users/scottmcpherson/Sites/phpsites/projectx/application/models/db.php on line 91 error

这是我创建的类，减去了一些与此问题无关的方法:

<?php 
require_once("../config/main.php");

class Database{

protected static $dbFields = array('username', 'password');
public $db;
public $tableName = 'users';
public $id = 1;
public $username = "Jonny";
public $password = "Appleseed";

public function __construct() {
    $this->connect();
}
public function connect(){
try {
    $this->db = new PDO("mysql:host=".DB_SERVER."; dbname=".DB_NAME, DB_USER, DB_PASS);

    } catch (PDOException $e) {
    echo 'Connection failed: ' . $e->getMessage();
    }
}
public function properties() {
    $properties = array();
    foreach (self::$dbFields as $field) {
        if (isset($this->field) || property_exists($this, $field)) {
            $properties[$field] = $this->$field;            
        }
    }
    return $properties;
}

public function propertyValues() {  
    $property = $this->properties();
    $propertyValues = array();
    foreach ($property as $key => $value) {
        $propertyValues = ":" . implode(", :", array_keys($property));
    }
    return $propertyValues;
}
public function polishedVals(){
       // The end result of this function is:
       // username=:username, password=:password
    $props = $this->properties();
    $phaseOne = array();
    foreach ($props as $key => $value) {
        $phaseOne[$key] = ":".$key;
    }
        $phaseTwo = array();
        foreach ($phaseOne as $key => $value) {
            $phaseTwo[] = "{$key}={$value}";
        }
        $polishedVals = implode(", ", $phaseTwo);
    return $polishedVals;
}
public function update(){

    $stmt  = "UPDATE ". $this->tableName." SET ";
    $stmt .= $this->polishedVals();
    $stmt .= "WHERE id=" . $this->id;   
    $stmt  = $this->db->prepare($stmt);
    if($stmt->execute($this->properties())) {
        echo "yes";
    } else {
        echo "error ";
    }
}
}

$database = new Database();

echo$database->update();


 ?>

将所有变量替换为实际值后，我使用 update() 方法得到的结果将如下所示:

public function update(){

    $stmt  = "UPDATE users SET ";
    $stmt .= "username=:username, password=:password ";
    $stmt .= "WHERE id=1";  
    $stmt  = $this->db->prepare($stmt);
    if($stmt->execute($this->properties())) {
        echo "yes";
    } else {
        echo "error ";
    }
}

除了发现此问题之外，如果您发现此代码有任何其他问题，请告诉我。我对 PHP 还是个新手。

编辑:我现在创建了一个新方法，将 : 添加到属性数组中每个键的开头:

public function colProperties(){
    $properties = $this->properties();
    $withCols = array();
    foreach($properties as $key => $value){
        $withCols[":".$key] = $value;

    }
    return $withCols;
}

所以我的 update() 方法现在看起来像: 公共(public)函数 update(){

    $stmt  = "UPDATE ". $this->tableName." SET ";
    $stmt .= $this->polishedVals();
    $stmt .= "WHERE id=" . $this->id;   
    $stmt  = $this->db->prepare($stmt);

    if($stmt->execute($this->colProperties())) {
        echo "yes";
    } else {
        echo "error ";
    }
}

如果我 var_dump($this->colProperties) 我得到: 数组(2){ [“:用户名”] =>字符串(5)“乔尼”[“:密码”]=>字符串(9)“Appleseed”} 并且仍然遇到相同的错误。

Answer 1

我认为将参数传递给 UPDATE 查询不需要与 SELECT 不同的方法。信息在 PDOStatement->execute()手册页应适用:

<?php
/* Execute a prepared statement by passing an array of insert values */
$calories = 150;
$colour = 'red';
$sth = $dbh->prepare('SELECT name, colour, calories
    FROM fruit
    WHERE calories < :calories AND colour = :colour');
$sth->execute(array(':calories' => $calories, ':colour' => $colour));
?>

您正在使用命名参数，因此 execute() 需要一个关联数组。使用var_dump()在 execute() 之前显示 $this->properties():

var_dump($this->properties())

确保您的 key 完全匹配。