我很好奇是否有可能使用PDO将值数组绑定到占位符。这里的用例试图传递一个值数组,以便与IN()条件一起使用。

我希望能够这样做:

<?php
$ids=array(1,2,3,7,8,9);
$db = new PDO(...);
$stmt = $db->prepare(
    'SELECT *
     FROM table
     WHERE id IN(:an_array)'
);
$stmt->bindParam('an_array',$ids);
$stmt->execute();
?>

并让PDO绑定并引用数组中的所有值。

目前我正在做:

<?php
$ids = array(1,2,3,7,8,9);
$db = new PDO(...);
foreach($ids as &$val)
    $val=$db->quote($val); //iterate through array and quote
$in = implode(',',$ids); //create comma separated list
$stmt = $db->prepare(
    'SELECT *
     FROM table
     WHERE id IN('.$in.')'
);
$stmt->execute();
?>

这当然是工作,但只是想知道是否有一个内置的解决方案,我错过了?


当前回答

您使用的是什么数据库?在PostgreSQL中,我喜欢使用ANY(数组)。重复一下你的例子:

<?php
$ids=array(1,2,3,7,8,9);
$db = new PDO(...);
$stmt = $db->prepare(
    'SELECT *
     FROM table
     WHERE id = ANY (:an_array)'
);
$stmt->bindParam('an_array',$ids);
$stmt->execute();
?>

不幸的是,这是非常不可移植的。

在其他数据库中,您将需要像其他人提到的那样,创建自己的魔法。当然,您需要将该逻辑放入类/函数中,以使其在整个程序中可重用。看看PHP mysql_query页面上的注释。关于这个主题的更多想法和这个场景的示例。

其他回答

对我来说,更性感的解决方案是构造一个动态关联数组并使用它

// A dirty array sent by user
$dirtyArray = ['Cecile', 'Gilles', 'Andre', 'Claude'];

// we construct an associative array like this
// [ ':name_0' => 'Cecile', ... , ':name_3' => 'Claude' ]
$params = array_combine(
    array_map(
        // construct param name according to array index
        function ($v) {return ":name_{$v}";},
        // get values of users
        array_keys($dirtyArray)
    ),
    $dirtyArray
);

// construct the query like `.. WHERE name IN ( :name_1, .. , :name_3 )`
$query = "SELECT * FROM user WHERE name IN( " . implode(",", array_keys($params)) . " )";
// here we go
$stmt  = $db->prepare($query);
$stmt->execute($params);

我扩展了PDO,做一些类似stefs建议的事情,从长远来看,这对我来说更容易:

class Array_Capable_PDO extends PDO {
    /**
     * Both prepare a statement and bind array values to it
     * @param string $statement mysql query with colon-prefixed tokens
     * @param array $arrays associatve array with string tokens as keys and integer-indexed data arrays as values 
     * @param array $driver_options see php documention
     * @return PDOStatement with given array values already bound 
     */
    public function prepare_with_arrays($statement, array $arrays, $driver_options = array()) {

        $replace_strings = array();
        $x = 0;
        foreach($arrays as $token => $data) {
            // just for testing...
            //// tokens should be legit
            //assert('is_string($token)');
            //assert('$token !== ""');
            //// a given token shouldn't appear more than once in the query
            //assert('substr_count($statement, $token) === 1');
            //// there should be an array of values for each token
            //assert('is_array($data)');
            //// empty data arrays aren't okay, they're a SQL syntax error
            //assert('count($data) > 0');

            // replace array tokens with a list of value tokens
            $replace_string_pieces = array();
            foreach($data as $y => $value) {
                //// the data arrays have to be integer-indexed
                //assert('is_int($y)');
                $replace_string_pieces[] = ":{$x}_{$y}";
            }
            $replace_strings[] = '('.implode(', ', $replace_string_pieces).')';
            $x++;
        }
        $statement = str_replace(array_keys($arrays), $replace_strings, $statement);
        $prepared_statement = $this->prepare($statement, $driver_options);

        // bind values to the value tokens
        $x = 0;
        foreach($arrays as $token => $data) {
            foreach($data as $y => $value) {
                $prepared_statement->bindValue(":{$x}_{$y}", $value);
            }
            $x++;
        }

        return $prepared_statement;
    }
}

你可以这样使用它:

$db_link = new Array_Capable_PDO($dsn, $username, $password);

$query = '
    SELECT     *
    FROM       test
    WHERE      field1 IN :array1
     OR        field2 IN :array2
     OR        field3 = :value
';

$pdo_query = $db_link->prepare_with_arrays(
    $query,
    array(
        ':array1' => array(1,2,3),
        ':array2' => array(7,8,9)
    )
);

$pdo_query->bindValue(':value', '10');

$pdo_query->execute();

以下是我的解决方案:

$total_items = count($array_of_items);
$question_marks = array_fill(0, $total_items, '?');
$sql = 'SELECT * FROM foo WHERE bar IN (' . implode(',', $question_marks ). ')';

$stmt = $dbh->prepare($sql);
$stmt->execute(array_values($array_of_items));

注意array_values的使用。这可以修复键排序问题。

我正在合并id数组,然后删除重复的项。我是这样写的:

$ids = array(0 => 23, 1 => 47, 3 => 17);

那就是失败。

为了让答案更接近最初使用占位符绑定参数的问题,我做了一些进一步的处理。

这个答案必须在查询中使用的数组中进行两次循环。但它确实解决了为更有选择性的查询使用其他列占位符的问题。

//builds placeholders to insert in IN()
foreach($array as $key=>$value) {
    $in_query = $in_query . ' :val_' . $key . ', ';
}

//gets rid of trailing comma and space
$in_query = substr($in_query, 0, -2);

$stmt = $db->prepare(
    "SELECT *
     WHERE id IN($in_query)";

//pind params for your placeholders.
foreach ($array as $key=>$value) {
    $stmt->bindParam(":val_" . $key, $array[$key])
}

$stmt->execute();

使用postgres数组("{}")是一种非常简洁的方法:

$ids = array(1,4,7,9,45);
$param = "{".implode(', ',$ids)."}";
$cmd = $db->prepare("SELECT * FROM table WHERE id = ANY (?)");
$result = $cmd->execute(array($param));