public function __construct() {
		parent::__construct();

		$this->create_args['post_type'] = current( $this->attendee_types() );

		$this->default_args = array_merge( $this->default_args, [
			'post_type'   => $this->attendee_types(),
			'orderby'     => [ 'date', 'title', 'ID' ],
			'post_status' => 'any',
		] );

		// Add initial simple schema.
		$this->add_simple_meta_schema_entry( 'event', $this->attendee_to_event_keys(), 'meta_in' );
		$this->add_simple_meta_schema_entry( 'event__not_in', $this->attendee_to_event_keys(), 'meta_not_in' );
		$this->add_simple_meta_schema_entry( 'ticket', $this->attendee_to_ticket_keys(), 'meta_in' );
		$this->add_simple_meta_schema_entry( 'ticket__not_in', $this->attendee_to_ticket_keys(), 'meta_not_in' );
		$this->add_simple_meta_schema_entry( 'order', $this->attendee_to_order_keys(), 'meta_in' );
		$this->add_simple_meta_schema_entry( 'order__not_in', $this->attendee_to_order_keys(), 'meta_not_in' );
		$this->add_simple_meta_schema_entry( 'product_id', $this->attendee_to_ticket_keys(), 'meta_in' );
		$this->add_simple_meta_schema_entry( 'product_id__not_in', $this->attendee_to_ticket_keys(), 'meta_not_in' );
		$this->add_simple_meta_schema_entry( 'purchaser_name', $this->purchaser_name_keys(), 'meta_in' );
		$this->add_simple_meta_schema_entry( 'purchaser_name__not_in', $this->purchaser_name_keys(), 'meta_not_in' );
		$this->add_simple_meta_schema_entry( 'purchaser_name__like', $this->purchaser_name_keys(), 'meta_like' );
		$this->add_simple_meta_schema_entry( 'purchaser_email', $this->purchaser_email_keys(), 'meta_in' );
		$this->add_simple_meta_schema_entry( 'purchaser_email__not_in', $this->purchaser_email_keys(), 'meta_not_in' );
		$this->add_simple_meta_schema_entry( 'purchaser_email__like', $this->purchaser_email_keys(), 'meta_like' );
		$this->add_simple_meta_schema_entry( 'security_code', $this->security_code_keys(), 'meta_in' );
		$this->add_simple_meta_schema_entry( 'security_code__not_in', $this->security_code_keys(), 'meta_not_in' );
		$this->add_simple_meta_schema_entry( 'user', '_tribe_tickets_attendee_user_id', 'meta_in' );
		$this->add_simple_meta_schema_entry( 'user__not_in', '_tribe_tickets_attendee_user_id', 'meta_not_in' );
		$this->add_simple_meta_schema_entry( 'price', '_paid_price' );

		$this->schema = array_merge( $this->schema, [
			'optout'               => [ $this, 'filter_by_optout' ],
			'rsvp_status'          => [ $this, 'filter_by_rsvp_status' ],
			'rsvp_status__or_none' => [ $this, 'filter_by_rsvp_status_or_none' ],
			'provider'             => [ $this, 'filter_by_provider' ],
			'provider__not_in'     => [ $this, 'filter_by_provider_not_in' ],
			'event_status'         => [ $this, 'filter_by_event_status' ],
			'order_status'         => [ $this, 'filter_by_order_status' ],
			'order_status__not_in' => [ $this, 'filter_by_order_status_not_in' ],
			'price_min'            => [ $this, 'filter_by_price_min' ],
			'price_max'            => [ $this, 'filter_by_price_max' ],
			'has_attendee_meta'    => [ $this, 'filter_by_attendee_meta_existence' ],
			'checkedin'            => [ $this, 'filter_by_checkedin' ],
		] );

		$this->init_order_statuses();
	}