pub async fn fetch_optional<DB: DbMarker>(
        self,
        storage: &mut Connection<'_, DB>,
    ) -> DalResult<Option<PgRow>> {
        let (conn, tags) = storage.conn_and_tags();
        self.data.fetch(tags, self.query.fetch_optional(conn)).await
    }
Fetches an optional row using this query.
core/lib/db_connection/src/instrument.rs