First wordpress plugin making - plugins

Question

I am making my very first wordpress plugin in that I want to make table in my database when I activate the plugin. I write the code exactly what wordpress community said but it's not working. I tried the same several times but the results is the same. I also want to know my plugin showing 2 submenus in my main plugin menu, It's like
My Plugin
-- My Plugin
-- My Submenu Page
Please help I am very new to plugin development.
// Registering plugin
register_activation_hook(__FILE__, 'myplugin_activate');
//Deactivate plugin
register_deactivation_hook(__FILE__, 'myplugin_deactivate');
function myplugin_activate() {
global $wpdb, $table_prefix;
global $favoritethis_db_version;
$table_name = $table_prefix.
'my-plugin-table';
$charset_collate = $wpdb - > get_charset_collate();
if ($wpdb - > get_var("show tables like '$table_name'") != $table_name) {
require_once(ABSPATH.
'wp-admin/upgrade-functions.php');
$sql = "CREATE TABLE ".$table_name.
" (
id mediumint(9) NOT NULL AUTO_INCREMENT,
time datetime DEFAULT '0000-00-00 00:00:00'
NOT NULL,
name tinytext NOT NULL,
text text NOT NULL,
url varchar(55) DEFAULT ''
NOT NULL,
UNIQUE KEY id(id)
) $charset_collate;
";
}
require_once(ABSPATH.
'wp-admin/includes/upgrade.php');
dbDelta($sql);
}
function myplugin_deactivate() {
// Deactivation code here...
echo "<script>alert('Ohhh.. no baby the plugin is deactivated now..')</script>";
}

Answer 1

also I found the solution of the problem, I was facing as getting extra sub menu as same name as the main menu is.
Solution
//Main admin menus
add_action('admin_menu', 'add_my_custom_menu');
function add_my_custom_menu() {
//add an item to the menu
add_menu_page(
'My Plugin',
'My Plugin',
10,
plugin_dir_path(__FILE__).
'admin/plugin-form.php',
'',
plugin_dir_url(__FILE__).
'img/contact.png'
);
add_submenu_page(
'my-plugin-name/admin/plugin-form.php',
'Plugin Setting',
'Plugin Setting',
10,
plugin_dir_path(__FILE__).
'admin/plugin-form.php',
'myplugin_options_page'
);
add_submenu_page(
'my-plugin-name/admin/plugin-form.php',
'Plugin Entries',
'Plugin Entries',
10,
plugin_dir_path(__FILE__).
'admin/entries.php',
''
);
}
reason is that every first sub-menu's destination page/function will be the same as main menu destination.

Answer 2

ok I got the answer myself
// Registering plugin
register_activation_hook(__FILE__, 'myplugin_activate');
//Deactivate plugin
register_deactivation_hook(__FILE__, 'myplugin_deactivate');
function myplugin_activate() {
global $wpdb;
$table_name = $wpdb - > prefix.
'my-plugin-table';
//nstalled_ver = get_option('my-voting-version');
if ($wpdb - > get_var("show tables like '$table_name' ") != $table_name) {
require_once(ABSPATH.
'wp-admin/upgrade-functions.php');
$sql = "CREATE TABLE IF NOT EXISTS `".str_replace('`', '', $table_name).
"` (
id mediumint(9) NOT NULL AUTO_INCREMENT,
time datetime DEFAULT '0000-00-00 00:00:00'
NOT NULL,
name tinytext NOT NULL,
text text NOT NULL,
url varchar(55) DEFAULT ''
NOT NULL,
UNIQUE KEY id(id)
);
";
}
require_once(ABSPATH.
'wp-admin/includes/upgrade.php');
dbDelta($sql);
}