diesel::prelude

Trait CombineDsl

Source 
pub trait CombineDsl {
    type Query: Query;

    // Required methods
    fn union<Rhs>(self, rhs: Rhs) -> Union<Self, Rhs>
       where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>;
    fn union_all<Rhs>(self, rhs: Rhs) -> UnionAll<Self, Rhs>
       where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>;
    fn intersect<Rhs>(self, rhs: Rhs) -> Intersect<Self, Rhs>
       where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>;
    fn intersect_all<Rhs>(self, rhs: Rhs) -> IntersectAll<Self, Rhs>
       where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>;
    fn except<Rhs>(self, rhs: Rhs) -> Except<Self, Rhs>
       where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>;
    fn except_all<Rhs>(self, rhs: Rhs) -> ExceptAll<Self, Rhs>
       where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>;
}
Expand description

Extension trait to combine queries using a combinator like UNION, INTERSECT or EXCEPT with or without ALL rule for duplicates

Required Associated Types§

Source

type Query: Query

What kind of query does this type represent?

Required Methods§

Source

fn union<Rhs>(self, rhs: Rhs) -> Union<Self, Rhs>
where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>,

Combine two queries using a SQL UNION

§Examples
let data = users.select(user_name.nullable())
    .union(animals.select(animal_name).filter(animal_name.is_not_null()))
    .load(connection);

let expected_data = vec![
    Some(String::from("Jack")),
    Some(String::from("Sean")),
    Some(String::from("Tess")),
];
assert_eq!(Ok(expected_data), data);
Source

fn union_all<Rhs>(self, rhs: Rhs) -> UnionAll<Self, Rhs>
where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>,

Combine two queries using a SQL UNION ALL

Source

fn intersect<Rhs>(self, rhs: Rhs) -> Intersect<Self, Rhs>
where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>,

Combine two queries using a SQL INTERSECT

Source

fn intersect_all<Rhs>(self, rhs: Rhs) -> IntersectAll<Self, Rhs>
where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>,

Combine two queries using a SQL INTERSECT ALL

Source

fn except<Rhs>(self, rhs: Rhs) -> Except<Self, Rhs>
where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>,

Combine two queries using a SQL EXCEPT

Source

fn except_all<Rhs>(self, rhs: Rhs) -> ExceptAll<Self, Rhs>
where Rhs: AsQuery<SqlType = <Self::Query as Query>::SqlType>,

Combine two queries using a SQL EXCEPT ALL

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§

Source§

impl<S> CombineDsl for Alias<S>
where S: AliasSource, S::Target: Table, Self: AsQuery,

Source§

type Query = <Alias<S> as AsQuery>::Query

Source§

impl<T: Table> CombineDsl for T

Source§

type Query = <T as AsQuery>::Query