WordPress Custom Database Tables

activation.php

register_activation_hook( __FILE__, 'my_plugin_create_db' );
function my_plugin_create_db() {
	// Create DB Here
}

create.php

function my_plugin_create_db() {

	global $wpdb;
	$charset_collate = $wpdb->get_charset_collate();
	$table_name = $wpdb->prefix . 'my_analysis';

	$sql = "CREATE TABLE $table_name (
		id mediumint(9) NOT NULL AUTO_INCREMENT,
		time datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
		views smallint(5) NOT NULL,
		clicks smallint(5) NOT NULL,
		UNIQUE KEY id (id)
	) $charset_collate;";

	require_once( ABSPATH . 'wp-admin/includes/upgrade.php' );
	dbDelta( $sql );
}

update.php

function my_plugin_create_db() {

	global $wpdb;
  	$version = get_option( 'my_plugin_version', '1.0' );
	$charset_collate = $wpdb->get_charset_collate();
	$table_name = $wpdb->prefix . 'my_analysis';

	$sql = "CREATE TABLE $table_name (
		id mediumint(9) NOT NULL AUTO_INCREMENT,
		time datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
		views smallint(5) NOT NULL,
		clicks smallint(5) NOT NULL,
		UNIQUE KEY id (id)
	) $charset_collate;";

	require_once( ABSPATH . 'wp-admin/includes/upgrade.php' );
	dbDelta( $sql );
	
	if ( version_compare( $version, '2.0' ) < 0 ) {
		$sql = "CREATE TABLE $table_name (
		  id mediumint(9) NOT NULL AUTO_INCREMENT,
		  time datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
		  views smallint(5) NOT NULL,
		  clicks smallint(5) NOT NULL,
		  blog_id smallint(5) NOT NULL,
		  UNIQUE KEY id (id)
		) $charset_collate;";
		dbDelta( $sql );
	
	  	update_option( 'my_plugin_version', '2.0' );
		
	}

	
}

version.php

function my_plugin_create_db() {
  global $wpdb;
  $version = get_option( 'my_plugin_version', '1.0' );
  // ...
}