Trait IntoSelectTarget 

pub trait IntoSelectTarget {
    type Marker;
}

Determines the select marker from what was passed to .select().

The marker controls how row types are inferred:

• SelectStar — infer R from the table’s Select model
• SelectCols<C> — infer R from the column value types
• SelectExpr — R must be specified by the user

Implemented automatically for:

• () → SelectStar
• SQL<'a, V> → SelectExpr
• SQLExpr<'a, V, T, N, A> → SelectCols<(Self,)>
• Tuples (A, B, ...) → SelectCols<(A, B, ...)>
• Column ZSTs (proc macro generated)
• Table structs (proc macro generated) → SelectStar

Required Associated Types

type 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,)>

Implementors

impl<E> IntoSelectTarget for AliasedExpr<E>

where E: ExprValueType,

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

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

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

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

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

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

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

type Marker = SelectExpr