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。

当你有其他参数时，你可以这样做:

$ids = array(1,2,3,7,8,9);
$db = new PDO(...);
$query = 'SELECT *
            FROM table
           WHERE X = :x
             AND id IN(';
$comma = '';
for($i=0; $i<count($ids); $i++){
  $query .= $comma.':p'.$i;       // :p0, :p1, ...
  $comma = ',';
}
$query .= ')';

$stmt = $db->prepare($query);
$stmt->bindValue(':x', 123);  // some value
for($i=0; $i<count($ids); $i++){
  $stmt->bindValue(':p'.$i, $ids[$i]);
}
$stmt->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。

在MySQL和PDO中，我们可以使用JSON数组和JSON_CONTAINS() (https://dev.mysql.com/doc/refman/8.0/en/json-search-functions.html#function_json-contains)进行搜索。

$ids = [123, 234, 345, 456]; // Array of users I search
$ids = json_encode($ids); // JSON conversion

$sql = <<<SQL
    SELECT ALL user_id, user_login
    FROM users
    -- Cast is mandatory beaucause JSON_CONTAINS() waits JSON doc candidate
    WHERE JSON_CONTAINS(:ids, CAST(user_id AS JSON))
    SQL;

$search = $pdo->prepare($sql);
$search->execute([':ids' => $ids]);
$users = $search->fetchAll();

我们也可以使用JSON_TABLE() (https://dev.mysql.com/doc/refman/8.0/en/json-table-functions.html#function_json-table)进行更复杂的情况和JSON数据探索:

$users = [
    ['id' => 123, 'bday' => ..., 'address' => ...],
    ['id' => 234, 'bday' => ..., 'address' => ...],
    ['id' => 345, 'bday' => ..., 'address' => ...],
]; // I'd like to know their login

$users = json_encode($users);

$sql = <<<SQL
    SELECT ALL user_id, user_login
    FROM users
    WHERE user_id IN (
        SELECT ALL user_id
        FROM JSON_TABLE(:users, '$[*]' COLUMNS (
            -- Data exploration...
            -- (if needed I can explore really deeply with NESTED kword)
            user_id INT PATH '$.id',
            -- I could skip these :
            user_bday DATE PATH '$.bday',
            user_address TINYTEXT PATH '$.address'
        )) AS _
    )
    SQL;

$search = $pdo->prepare($sql);
$search->execute([':users' => $users]);
...

我有一个独特的问题，在将即将被弃用的MySQL驱动程序转换为PDO驱动程序时，我必须创建一个函数，该函数可以动态地从相同的参数数组中构建正常参数和INs。所以我很快就做了这个:

/**
 * mysql::pdo_query('SELECT * FROM TBL_WHOOP WHERE type_of_whoop IN :param AND siz_of_whoop = :size', array(':param' => array(1,2,3), ':size' => 3))
 *
 * @param $query
 * @param $params
 */
function pdo_query($query, $params = array()){

    if(!$query)
        trigger_error('Could not query nothing');

    // Lets get our IN fields first
    $in_fields = array();
    foreach($params as $field => $value){
        if(is_array($value)){
            for($i=0,$size=sizeof($value);$i<$size;$i++)
                $in_array[] = $field.$i;

            $query = str_replace($field, "(".implode(',', $in_array).")", $query); // Lets replace the position in the query string with the full version
            $in_fields[$field] = $value; // Lets add this field to an array for use later
            unset($params[$field]); // Lets unset so we don't bind the param later down the line
        }
    }

    $query_obj = $this->pdo_link->prepare($query);
    $query_obj->setFetchMode(PDO::FETCH_ASSOC);

    // Now lets bind normal params.
    foreach($params as $field => $value) $query_obj->bindValue($field, $value);

    // Now lets bind the IN params
    foreach($in_fields as $field => $value){
        for($i=0,$size=sizeof($value);$i<$size;$i++)
            $query_obj->bindValue($field.$i, $value[$i]); // Both the named param index and this index are based off the array index which has not changed...hopefully
    }

    $query_obj->execute();

    if($query_obj->rowCount() <= 0)
        return null;

    return $query_obj;
}

它仍然未经测试，但逻辑似乎是存在的。

经过一些测试，我发现:

PDO不喜欢’。’(如果你问我的话，我觉得这有点蠢) bindParam是错误函数，bindValue是正确函数。

简单来说:

//$db = new PDO(...);
//$ids = array(...);

$qMarks = str_repeat('?,', count($ids) - 1) . '?';
$sth = $db->prepare("SELECT * FROM myTable WHERE id IN ($qMarks)");
$sth->execute($ids);