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Php select语句的Wordpress值错误_Php_Mysql_Wordpress - Fatal编程技术网

Php select语句的Wordpress值错误

Php select语句的Wordpress值错误,php,mysql,wordpress,Php,Mysql,Wordpress,下面的代码一直在回显0,尽管我知道它不应该回显。有什么问题?回显查询并在phpmyadmin中运行,然后查看查询是否返回任何结果OK。我找到了解决办法。它应该是echo$numb[0]->event\u id。 $myEvents = $wpdb->prefix . 'Events'; $sql = "SELECT COALESCE(max(event_id),0) FROM $myEvents WHERE event_title = 'pd'"; $num

下面的代码一直在回显0,尽管我知道它不应该回显。有什么问题?

回显查询并在phpmyadmin中运行,然后查看查询是否返回任何结果OK。我找到了解决办法。它应该是echo$numb[0]->event\u id。
$myEvents = $wpdb->prefix . 'Events';

       $sql = "SELECT COALESCE(max(event_id),0) FROM $myEvents WHERE event_title = 'pd'";
        $numb = $wpdb->get_results($sql);
        $num = $numb->{'event_id'};
        echo $num;