public function set_query() {

		global $wpdb;

		$dates = $this->get_posted_dates();

		$student_ids = '';
		$students    = $this->get_posted_students();
		if ( $students ) {
			$student_ids .= 'AND user_id IN ( ' . implode( ', ', $students ) . ' )';
		}

		$lesson_ids = '';
		$products   = $this->get_posted_posts();

		if ( $products ) {
			$lesson_ids .= 'AND post_id IN ( ' . implode( ', ', $this->get_lesson_ids( $products ) ) . ' )';
		}

		$this->query_function = 'get_results';
		$this->output_type    = OBJECT;

		$this->query = "SELECT updated_date AS date
						FROM {$wpdb->prefix}lifterlms_user_postmeta AS upm
						JOIN {$wpdb->posts} AS p ON p.ID = upm.post_id
						WHERE
							    upm.meta_key = '_is_complete'
							AND p.post_type = 'lesson'
							AND upm.meta_value = 'yes'
							AND upm.updated_date BETWEEN CAST( %s AS DATETIME ) AND CAST( %s AS  DATETIME )
							{$student_ids}
							{$lesson_ids}
						;";

		$this->query_vars = array(
			$this->format_date( $dates['start'], 'start' ),
			$this->format_date( $dates['end'], 'end' ),
		);

	}