Trait IntoSelectTarget 

pub trait IntoSelectTarget {
    type Marker;
}

Something that can be passed to .select(...); picks the select marker.

The marker decides how the row type is inferred:

• SelectStar: the table’s select model;
• SelectCols<C>: a tuple of the columns’ value types;
• SelectExpr: the caller names the row type;
• SelectAs<R>: the FromRow struct R.

Implemented for:

• () -> SelectStar
• SQL<'a, V> -> SelectExpr
• SQLExpr<'a, V, T, N, A, S> -> SelectCols<(Self,)>
• tuples (A, B, ...) -> SelectCols<(A, B, ...)>
• columns and tables (generated by the table macros)
• FromRow selectors (generated by the FromRow derives) -> SelectAs<R>

Required Associated Types

type Marker

The select marker.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl IntoSelectTarget for ()

select(()) → SelectStar — infer row type from the table.

type Marker = SelectStar

impl<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15> IntoSelectTarget for (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15)>

impl<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14> IntoSelectTarget for (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14)>

impl<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13> IntoSelectTarget for (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13)>

impl<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12> IntoSelectTarget for (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12)>

impl<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11> IntoSelectTarget for (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11)>

impl<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10> IntoSelectTarget for (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10)>

impl<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9> IntoSelectTarget for (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5, T6, T7, T8, T9)>

impl<T0, T1, T2, T3, T4, T5, T6, T7, T8> IntoSelectTarget for (T0, T1, T2, T3, T4, T5, T6, T7, T8)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5, T6, T7, T8)>

impl<T0, T1, T2, T3, T4, T5, T6, T7> IntoSelectTarget for (T0, T1, T2, T3, T4, T5, T6, T7)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5, T6, T7)>

impl<T0, T1, T2, T3, T4, T5, T6> IntoSelectTarget for (T0, T1, T2, T3, T4, T5, T6)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5, T6)>

impl<T0, T1, T2, T3, T4, T5> IntoSelectTarget for (T0, T1, T2, T3, T4, T5)

type Marker = SelectCols<(T0, T1, T2, T3, T4, T5)>

impl<T0, T1, T2, T3, T4> IntoSelectTarget for (T0, T1, T2, T3, T4)

type Marker = SelectCols<(T0, T1, T2, T3, T4)>

impl<T0, T1, T2, T3> IntoSelectTarget for (T0, T1, T2, T3)

type Marker = SelectCols<(T0, T1, T2, T3)>

impl<T0, T1, T2> IntoSelectTarget for (T0, T1, T2)

type Marker = SelectCols<(T0, T1, T2)>

impl<T0, T1> IntoSelectTarget for (T0, T1)

type Marker = SelectCols<(T0, T1)>

impl<T0> IntoSelectTarget for (T0,)

type Marker = SelectCols<(T0,)>

impl<T: IntoSelectTarget + ?Sized> IntoSelectTarget for &T

type Marker = <T as IntoSelectTarget>::Marker

Implementors

impl<E, Name> IntoSelectTarget for NamedExpr<E, Name>

where E: ExprValueType,

type Marker = SelectCols<(NamedExpr<E, Name>,)>

impl<E> IntoSelectTarget for AliasedExpr<E>

where E: ExprValueType,

type Marker = SelectCols<(AliasedExpr<E>,)>

impl<Name, Output> IntoSelectTarget for DerivedField<Name, Output>

where Name: Tag, Output: ProjectionOutput + ExprValueType,

type Marker = SelectCols<(DerivedField<Name, Output>,)>

impl<V: SQLParam, T, N, A, S> IntoSelectTarget for SQLExpr<'_, V, T, N, A, S>

where T: DataType, N: Nullability, A: AggregateKind,

select(typed_expr) → SelectCols<(Expr,)> — single typed expression.

type Marker = SelectCols<(SQLExpr<'_, V, T, N, A, S>,)>

impl<V: SQLParam> IntoSelectTarget for SQL<'_, V>

select(sql!(...)) → SelectExpr — user must specify row type.

type Marker = SelectExpr