我正在尝试获取具有多个where条件的数据，但我不知道where是问题所在。此查询发送空白输出。任何帮助。
$user1 = $wpdb->get_results("select product,checked_by,submit_date,unit_data,temperature_in,temperature_out,time_in, time_out,category from diary_user_form_storage where category_name=\'opening OR closing\' order by submit_date");
最合适的回答,由SO网友:Sneha Agarwal 整理而成
你的语法哪里错了应该是
$user1 = $wpdb->get_results("select product,checked_by,submit_date,unit_data,temperature_in,temperature_out,time_in, time_out,category from diary_user_form_storage where category_name=\'opening\' OR category_name=\'closing\' order by submit_date");
