Error I get when using raw sql

raw-sql-diesel-rust.rs

#[derive(Queryable, Debug)]
pub struct DownloadAnswer {
    pub timestamp: NaiveDateTime,
    pub email: String,
    pub requester: String,
    pub answers: Vec<String>
}

impl FromSql<(diesel::types::Timestamp, diesel::types::Text, diesel::types::Text, diesel::types::Array<diesel::types::Text>), diesel::pg::Pg> for DownloadAnswer {
    fn from_sql(bytes: Option<&[u8]>) -> Result<Self, Box<Error + Send + Sync>> {

        println!("{:?}", bytes);

        // Not really sure how to parse this
        Ok(DownloadAnswer {
            timestamp: UTC::now().naive_local(),
            email:     "[email protected]".to_owned(),
            requester: "Patrick".to_owned(),
            answers:   vec!("foo".to_owned(), "bar".to_owned())
        })
    }
}

let sql = format!(r"select created_at as timestamp,
                           a.email as email,
                           r.name as requester,
                           answer as answers
                              from advice_requests
                                  join people as r on advice_requests.requester_id = r.id
                                  join people as a on advice_requests.advisor_id = a.id
                                  join answers on answers.advice_request_id = advice_requests.id
                               where advice_requests.questionnaire_id = '{the_id}'::uuid;", the_id = questionnaire_id);
println!("The sql was: {}", sql);

let query = diesel::expression::sql(&sql);

let result = query.get_results::<Vec<DownloadAnswer>>(self.connection);

println!("{:?}", result);

Example result from running that query in PostgreSQL cli:

2017-04-12 17:34:53.250539 | [email protected] | Bob Sample | First answer from A
2017-04-12 17:34:53.250539 | [email protected] | Bob Sample | Second answer from A
2017-04-12 17:35:04.718267 | [email protected] | Bob Sample | First answer from B
2017-04-12 17:35:04.718267 | [email protected] | Bob Sample | Second answer from B
2017-04-12 17:35:20.284857 | [email protected] | Bob Sample | First answer from C
2017-04-12 17:35:20.284857 | [email protected] | Bob Sample | Second answer from C