Trait BelongingToDsl

pub trait BelongingToDsl<T> {
    type Output;

    // Required method
    fn belonging_to(other: T) -> Self::Output;
}

Constructs a query that finds record(s) based on directional association with other record(s).

Example

let sean = users.filter(name.eq("Sean")).first::<User>(connection)?;
let tess = users.filter(name.eq("Tess")).first::<User>(connection)?;

let seans_posts = Post::belonging_to(&sean)
    .select(title)
    .load::<String>(connection)?;
assert_eq!(vec!["My first post", "About Rust"], seans_posts);

// A vec or slice can be passed as well
let more_posts = Post::belonging_to(&vec![sean, tess])
    .select(title)
    .load::<String>(connection)?;
assert_eq!(vec!["My first post", "About Rust", "My first post too"], more_posts);

Required Associated Types

type Output

The query returned by belonging_to

Required Methods

fn belonging_to(other: T) -> Self::Output

Get the record(s) belonging to record(s) other

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<'a, Parent, Child> BelongingToDsl<&'a [Parent]> for Child

where &'a Parent: Identifiable, Child: HasTable + BelongsTo<Parent>, Vec<<&'a Parent as Identifiable>::Id>: AsInExpression<<Child::ForeignKeyColumn as Expression>::SqlType>, <Child as HasTable>::Table: FilterDsl<EqAny<Child::ForeignKeyColumn, Vec<<&'a Parent as Identifiable>::Id>>>, Child::ForeignKeyColumn: ExpressionMethods, <Child::ForeignKeyColumn as Expression>::SqlType: SqlType,

type Output = <<Child as HasTable>::Table as FilterDsl<Grouped<In<<Child as BelongsTo<Parent>>::ForeignKeyColumn, <Vec<<&'a Parent as Identifiable>::Id> as AsInExpression<<<Child as BelongsTo<Parent>>::ForeignKeyColumn as Expression>::SqlType>>::InExpression>>>>::Output

impl<'a, Parent, Child> BelongingToDsl<&'a Vec<Parent>> for Child

where Child: BelongingToDsl<&'a [Parent]>,

type Output = <Child as BelongingToDsl<&'a [Parent]>>::Output

impl<'a, Parent, Child> BelongingToDsl<(&'a [Parent], &'a [Parent])> for Child

where &'a Parent: Identifiable, Child: HasTable + BelongsTo<Parent>, Vec<<&'a Parent as Identifiable>::Id>: AsInExpression<<Child::ForeignKeyColumn as Expression>::SqlType>, <Child as HasTable>::Table: FilterDsl<EqAny<Child::ForeignKeyColumn, Vec<<&'a Parent as Identifiable>::Id>>>, Child::ForeignKeyColumn: ExpressionMethods, <Child::ForeignKeyColumn as Expression>::SqlType: SqlType,

type Output = <<Child as HasTable>::Table as FilterDsl<Grouped<In<<Child as BelongsTo<Parent>>::ForeignKeyColumn, <Vec<<&'a Parent as Identifiable>::Id> as AsInExpression<<<Child as BelongsTo<Parent>>::ForeignKeyColumn as Expression>::SqlType>>::InExpression>>>>::Output

impl<'a, Parent, Child> BelongingToDsl<&'a Parent> for Child

where &'a Parent: Identifiable, Child: HasTable + BelongsTo<Parent>, <&'a Parent as Identifiable>::Id: AsExpression<<Child::ForeignKeyColumn as Expression>::SqlType>, Child::Table: FilterDsl<Eq<Child::ForeignKeyColumn, <&'a Parent as Identifiable>::Id>>, Child::ForeignKeyColumn: ExpressionMethods, <Child::ForeignKeyColumn as Expression>::SqlType: SqlType,

type Output = <<Child as HasTable>::Table as FilterDsl<Grouped<Eq<<Child as BelongsTo<Parent>>::ForeignKeyColumn, <<&'a Parent as Identifiable>::Id as AsExpression<<<Child as BelongsTo<Parent>>::ForeignKeyColumn as Expression>::SqlType>>::Expression>>>>::Output