Trait ScopeEntry 

pub trait ScopeEntry {
    type Key;
    type Nullable: Nullability;
    type Sources;
}

Something that can be listed in FROM or JOIN: a table, view, alias, derived table, CTE, or raw SQL.

Table, view, and alias macros implement this for you. A column’s Sources names its source as Src<T>, and the scope check looks up T::Key in the query’s scope.

Tables and views are keyed by their SQL name (TableKey). Aliased sources (Table::alias::<Tag>(), derived tables, CTEs) are keyed by AliasKey<Tag>, because SQL resolves their columns by alias name.

Required Associated Types

type Key

How columns refer to this source: a TableKey or an AliasKey.

type Nullable: Nullability

Null when an outer join can leave this source NULL.

type Sources

Sources this source reads itself, such as the tables a derived table’s subquery reads from an outer query. They resolve against the enclosing query (or, for a LATERAL join, the sources joined before it). Tables and views read nothing (()).

Dyn Compatibility

This trait is dyn compatible.

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

Implementations on Foreign Types

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

type Key = <T as ScopeEntry>::Key

type Nullable = <T as ScopeEntry>::Nullable

type Sources = <T as ScopeEntry>::Sources

Implementors

impl<T: ScopeEntry> ScopeEntry for OuterJoined<T>

type Key = <T as ScopeEntry>::Key

type Nullable = Null

type Sources = ()

impl<Tag> ScopeEntry for AliasKey<Tag>

type Key = AliasKey<Tag>

type Nullable = NonNull

type Sources = ()

impl<V: SQLParam, Name, Projection, Query: ExprSources> ScopeEntry for Derived<'_, V, Name, Projection, Query>

type Key = AliasKey<Name>

type Nullable = NonNull

type Sources = <Query as ExprSources>::Sources

impl<V: SQLParam, Table: ScopeEntry, Query> ScopeEntry for CTEView<'_, V, Table, Query>

type Key = <Table as ScopeEntry>::Key

type Nullable = <Table as ScopeEntry>::Nullable

type Sources = ()

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

type Key = RawSource

type Nullable = NonNull

type Sources = ()