在我的插件代码中，我从两个表中提取表id。id是从一个表中提取的，而不是从另一个表中提取的，在这两种情况下我都会出错。当我使用这些查询时，它们在mysql上工作。有什么想法吗？代码在下面，输出在下面。id是从wp\\U shclass表中提取的，而不是从wp\\U shinstructor表中提取的。有什么想法吗？我已经盯着这几天了，不知道出了什么问题。我正在使用wp 3.3.1

function shmain_admin(){
if (!current_user_can(\'manage_options\'))  {
wp_die( __(\'You do not have sufficient permissions to access this page.\') );
}

echo "Hello class";
global $wpdb;
$shrow = $wpdb->get_row("select * from wp_shclass ORDER BY classid DESC LIMIT 1", ARRAY_A);  
$shclassid = $shrow[\'classid\'];
echo "<br> this is " . $shclassid;
$wpdb->show_errors();
$wpdb->print_error();
echo "<br> Hello instructor";
$shrow = $wpdb->get_row("select * from wp_shinstructor ORDER BY instructorid DESC LIMIT 1", ARRAY_A);  
$shinstructorid = $shrow[\'instructorid\'];
echo "<br> this is " . $shinstructorid;
$wpdb->print_error();
}

function shmain_admin_action(){
add_menu_page(\'sh main\', \'main\', \'manage_options\',\'shmain\', \'shmain_admin\');
}

add_action(\'admin_menu\',\'shmain_admin_action\');

你好，我是8

WordPress database error: []
select * from wp_shclass ORDER BY classid DESC LIMIT 1

WordPress database error: []
select * from wp_shinstructor ORDER BY instructorid DESC LIMIT 1