Trait diesel::prelude::AppearsOnTable[][src]

pub trait AppearsOnTable<QS: ?Sized>: Expression { }
Expand description

Indicates that all elements of an expression are valid given a from clause.

This is used to ensure that users.filter(posts::id.eq(1)) fails to compile. This constraint is only used in places where the nullability of a SQL type doesn’t matter (everything except select and returning). For places where nullability is important, SelectableExpression is used instead.

Implementations on Foreign Types