长话短说：我需要从WordPress创建的自定义表中检索数据，并向相关帖子添加/更新元数据（post\\u type=product）。我可以通过post元数据（\\u sku）匹配post（产品）和自定义表字段，这是我查询的关键
为了给您提供更多的上下文，下面是我的查询：
SELECT * FROM wpfx_custom_table a
left join wpfx_postmeta b
on a.custom_key_id=b.meta_value
WHERE b.meta_key = \'_sku\'
ORDER BY a.custom_date DESC
LIMIT 1
我尝试过这个方法，但不起作用：
function update_custom_post_meta_data() {
global $wpdb;
global $post;
$args = array(
\'posts_per_page\' => -1,
\'post_type\' => \'products\',
\'suppress_filters\' => true,
\'meta_key\' => \'_sku\'
);
$posts_array = get_posts( $args );
foreach($posts_array as $post_array) {
$post_array->the_post();
$post_id = $post_array->ID;
$post_sku = get_post_meta($post_id,\'_sku\',true);
$CustomTable = $wpdb->prefix.\'custom_table\';
$results = $wpdb->get_results ( "SELECT * FROM CustomTable WHERE `custom_key_id` = $meme_sku ORDER BY `custom_date` DESC LIMIT 1");
foreach($results as $result){
$custom_meta_value = $result->custom_column1;
add_post_meta($post_id, \'custom_meta_key\', $custom_meta_value);
}
update_post_meta($post_id, \'custom_meta_key\', $custom_meta_value);
}
}
提前谢谢你
最合适的回答,由SO网友:shanebp 整理而成
您的功能中有几个问题。不要在sql中使用反勾号。不要在字段名称周围加引号。您使用get_results 具有LIMIT 1 当您只需要单行中单个列的值时。而您使用$meme_sku 而不是$post_sku ?只是猜测一下这个例子，它可能会起作用。。。
function update_custom_post_meta_data() {
global $wpdb;
$args = array(
\'posts_per_page\' => -1,
\'post_type\' => \'product\',
\'suppress_filters\' => true,
\'meta_key\' => \'_sku\'
);
$posts_array = get_posts( $args );
$customTable = $wpdb->prefix.\'custom_table\';
foreach($posts_array as $post) {
$post_id = $post->ID;
$post_sku = get_post_meta($post_id,\'_sku\',true);
$result = $wpdb->get_var( "SELECT custom_column1 FROM $customTable WHERE custom_key_id = $post_sku");
if ( $result != NULL ) {
update_post_meta($post_id, \'custom_meta_key\', $result);
}
}
}
