Trait diesel::prelude::OrderDsl
[−]
[src]
pub trait OrderDsl<Expr: Expression>: AsQuery {
type Output: AsQuery<SqlType = Self::SqlType>;
fn order(self, expr: Expr) -> Self::Output;
}Sets the order clause of a query. If there was already a order clause, it
will be overridden. The expression passed to order must actually be valid
for the query. See also:
.desc()
and .asc()
Ordering by multiple columns can be achieved by passing a tuple of those columns.
This is automatically implemented for the various query builder types.
Examples
use self::users::dsl::{users, id, name}; let connection = establish_connection(); connection.execute("INSERT INTO users (name) VALUES ('Saul'), ('Steve'), ('Stan')").unwrap(); // load all users' names, ordered by their name descending let ordered_names: Vec<String> = users.select(name).order(name.desc()).load(&connection).unwrap(); assert_eq!(vec![String::from("Steve"), String::from("Stan"), String::from("Saul")], ordered_names); connection.execute("INSERT INTO users (name) VALUES ('Stan')").unwrap(); let ordered_name_id_pairs = users.select((name, id)).order((name.asc(), id.desc())).load(&connection).unwrap(); assert_eq!(vec![(String::from("Saul"), 3), (String::from("Stan"), 6), (String::from("Stan"), 5), (String::from("Steve"), 4)], ordered_name_id_pairs);