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为什么db_placeholder为我的查询返回空字符串?

drupal-6 drupal

Mike Munroe · 技术社区 · 15 年前

我正在查询中使用db_placeholder替换字符串数组。

$paths = array("commentary_analysis/18", "commentary_analysis/16", "commentary_analysis/95", "commentary_analysis/89");

$query = "SELECT DISTINCT a.uid, u.mail FROM {alerts} a JOIN {users} u on u.uid = a.uid WHERE u.mail IS NOT NULL AND u.mail != '' AND u.status = 1 AND a.status = %d AND a.view_path IN (" . db_placeholders($paths, 'text') . ") ORDER BY a.uid ASC";

$users_to_notify = db_query($query, $alert_status, $paths);

当我知道应该返回结果时,查询不会返回结果。我调试了查询以查看正在运行的确切查询。正在运行的查询是,

SELECT DISTINCT a.uid, u.mail FROM alerts a JOIN users u on u.uid = a.uid WHERE u.mail IS NOT NULL AND u.mail != '' AND u.status = 1 AND a.status = 1 AND a.view_path IN ('','','','') ORDER BY a.uid ASC

注意, a.view_path IN ('','','','') . 这就是问题所在。从我所看到的来看,我希望db_placeholder使用正确的语法。

有人能告诉我为什么我要使用db_placeholder返回吗? ('','','','') 而不是 ("commentary_analysis/18", "commentary_analysis/16", "commentary_analysis/95", "commentary_analysis/89") ?

3 回复 | 直到 15 年前

Dave Reid 15 年前

问题是,您可以将所有单值参数传递给db_查询,也可以传递一个参数数组。您的代码正在传递一个值,然后是一个数组,Drupal没有那么灵活。

试试这个:

$paths = array(
  'commentary_analysis/18',
  'commentary_analysis/16',
  'commentary_analysis/95',
  'commentary_analysis/89',
);

$query = "SELECT DISTINCT a.uid, u.mail
          FROM {alerts} a
          JOIN {users} u on u.uid = a.uid
          WHERE u.mail IS NOT NULL
            AND u.mail != ''
            AND u.status = 1
            AND a.status = %d
            AND a.view_path IN (" . db_placeholders($paths, 'varchar') . ")
          ORDER BY a.uid ASC";

$args = array_merge(array($alert_status), $paths);
$users_to_notify = db_query($query, $args);

Mike Munroe 15 年前

交换查询中db_查询修饰符的顺序可以解决问题。

  $query = "SELECT DISTINCT a.uid, u.mail FROM {ifrmarkets_alerts} a JOIN {users} u on u.uid = a.uid WHERE u.mail IS NOT NULL AND u.mail != '' AND a.view_path IN (" . db_placeholders($paths, 'varchar') . ") AND u.status = 1 AND a.status = %d ORDER BY a.uid ASC";
  $users_to_notify = db_query($query, $paths, $alert_status);

-1

Ran Bar-Zik 15 年前

首先,在Drupal7中不推荐使用db_占位符,因此您应该考虑不使用它。这是浪费记忆的功能。

尝试使用varchar数据类型:

$query = "SELECT DISTINCT a.uid, u.mail FROM {alerts} a JOIN {users} u on u.uid = a.uid WHERE u.mail IS NOT NULL AND u.mail != '' AND u.status = 1 AND a.status = %d AND a.view_path IN (" . db_placeholders($paths, 'varchar') . ") ORDER BY a.uid ASC"