我有多个自定义日期和时间字段的事件帖子。为了获取本周发生的所有事件，我正在查询不同的日期字段。这是我的代码：
$today=date("Y-m-d");
$nextweek= date("Y-m-d", strtotime("+7 days"));
$args2 = array(
\'post_type\' => \'post\',
\'meta_query\' => array(
\'relation\' => \'OR\',
array(
\'key\' => \'date2\',
\'value\' => array( $today, $nextweek ),
\'compare\' => \'BETWEEN\'
),
array(
\'key\' => \'date3\',
\'value\' => array( $today, $nextweek ),
\'compare\' => \'BETWEEN\'
),
array(
\'key\' => \'date1\',
\'value\' => array( $today, $nextweek ),
\'compare\' => \'BETWEEN\'
)
)
);
$query2 = new WP_Query( $args2 ); ?>
在这之后放置var\\u dump（$query2->request）时，我得到以下字符串：
SELECT SQL_CALC_FOUND_ROWS wp_posts.ID
FROM wp_posts
INNER JOIN wp_postmeta ON (wp_posts.ID = wp_postmeta.post_id)
INNER JOIN wp_postmeta AS mt1 ON (wp_posts.ID = mt1.post_id)
INNER JOIN wp_postmeta AS mt2 ON (wp_posts.ID = mt2.post_id)
WHERE 1=1 AND wp_posts.post_type = \'post\'
AND (wp_posts.post_status = \'publish\' OR wp_posts.post_status = \'private\')
AND (
(wp_postmeta.meta_key = \'date2\' AND CAST(wp_postmeta.meta_value AS CHAR) BETWEEN \'2013-05-21\' AND \'2013-05-28\')
OR (mt1.meta_key = \'date3\' AND CAST(mt1.meta_value AS CHAR) BETWEEN \'2013-05-21\' AND \'2013-05-28\')
OR (mt2.meta_key = \'date1\' AND CAST(mt2.meta_value AS CHAR) BETWEEN \'2013-05-21\' AND \'2013-05-28\')
)
GROUP BY wp_posts.ID
ORDER BY wp_posts.post_date DESC LIMIT 0, 10
这是正确的帖子，但现在我想对date1字段上的结果进行排序。我试过了，但没用。我最终发布了所有事件，但也没有进行排序。我还尝试了orderby的“meta\\u值”，但运气不佳。date1字段中的值为日期格式YYYY MM DDA，如有任何帮助，将不胜感激。
$args2 = array(
\'order\' => \'ASC\',
\'meta_key\' => \'date1\',
\'orderby\' => \'meta_value_num\',
\'post_type\' => \'post\',
\'meta_query\' => array(
\'relation\' => \'OR\',
array(
\'key\' => \'date2\',
\'value\' => array( $today, $nextweek ),
\'compare\' => \'BETWEEN\'
),
array(
\'key\' => \'date3\',
\'value\' => array( $today, $nextweek ),
\'compare\' => \'BETWEEN\'
),
array(
\'key\' => \'date1\',
\'value\' => array( $today, $nextweek ),
\'compare\' => \'BETWEEN\',
)
)
);
$query2 = new WP_Query( $args2 ); ?>
当我将var\\u dump（$query2->request）放在这之后时，我得到：
SELECT SQL_CALC_FOUND_ROWS wp_posts.ID
FROM wp_posts
INNER JOIN wp_postmeta ON wp_posts.ID = wp_postmeta.post_id
INNER JOIN wp_postmeta AS mt1 ON (wp_posts.ID = mt1.post_id)
INNER JOIN wp_postmeta AS mt2 ON (wp_posts.ID = mt2.post_id)
INNER JOIN wp_postmeta AS mt3 ON (wp_posts.ID = mt3.post_id)
WHERE 1=1
AND wp_posts.post_type = \'post\'
AND (wp_posts.post_status = \'publish\' OR wp_posts.post_status = \'private\')
AND (wp_postmeta.meta_key = \'date1\'
OR (mt1.meta_key = \'date2\' AND CAST(mt1.meta_value AS CHAR) BETWEEN \'2013-05-21\' AND \'2013-05-28\')
OR (mt2.meta_key = \'date3\' AND CAST(mt2.meta_value AS CHAR) BETWEEN \'2013-05-21\' AND \'2013-05-28\')
OR (mt3.meta_key = \'date1\' AND CAST(mt3.meta_value AS CHAR) BETWEEN \'2013-05-21\' AND \'2013-05-28\')
)
GROUP BY wp_posts.ID
ORDER BY wp_postmeta.meta_value+0 ASC LIMIT 0, 10
SO网友:s_ha_dum
您的元字段是JOINing as公司mt* 该查询中的别名。寻找以下线条：
INNER JOIN wp_postmeta AS mt1 ON ...
但是
ORDER BY 参数为
wp_postmeta.meta_value, 这其实没什么意义。如果这不是一个bug，我称之为糟糕的设计或非常有限的设计，但请继续。
要特别针对你的一个元价值，第一个，你需要ORDER BY 要成为。。。
ORDER BY mt1.meta_value
你不想
meta_value_num, 顺便说一下，因为你没有数字。那里有破折号。MySQL将把日期“2013-12-15”+0解释为“2013”。放
SELECT (\'2013-12-15\')+0 进入PhpMyAdmin的SQL面板并运行查询。
要对现有数据执行此操作，需要为查询创建一个过滤器。向查询中添加参数。。。
$args2 = array(
\'my_orderby_field\' => \'mt1\',
\'order\' => \'ASC\',
\'meta_key\' => \'date1\',
\'orderby\' => \'meta_value\',
/* ... the rest */
function order_by_one_meta($orderby,$qry) {
$myorder = $qry->get(\'my_orderby_field\');
if (!empty($myorder)) {
global $wpdb;
$orderby = str_replace($wpdb->postmeta,$myorder,$orderby);
}
return $orderby;
}
add_filter(\'posts_orderby\',\'order_by_one_meta\',100,2);
将自己的字段添加到查询中是一种黑客行为。我不知道它是设计出来的，或者是无意中产生的副作用，所以它确实算是一段有点危险的代码。另一种方法是创建回调：
function order_by_one_meta($orderby) {
$orderby = str_replace($wpdb->postmeta,$myorder,$orderby);
return $orderby;
}
应用它，然后在需要的地方将其移除。
add_filter(\'posts_orderby\',\'order_by_one_meta\',100);
$query2 = new WP_Query( $args2 );
remove_filter(\'posts_orderby\',\'order_by_one_meta\',100);
不那么危险，也没那么有趣(
我无法测试这一点，因为我在数据库中没有您的数据，但SQL应该是正确的。
我不知道为什么你需要多个日期键。多次使用同一个键_scheduled_event_dates-- 应该会给您同样的效果，并且会使查询和代码更加高效。
