Trait diesel::expression_methods::PgExpressionMethods

source · [−]
pub trait PgExpressionMethods: Expression + Sized {
    fn is_not_distinct_from<T>(
        self, 
        other: T
    ) -> IsNotDistinctFrom<Self, T::Expression>
    where
        T: AsExpression<Self::SqlType>,
    { ... }

    fn is_distinct_from<T>(
        self, 
        other: T
    ) -> IsDistinctFrom<Self, T::Expression>
    where
        T: AsExpression<Self::SqlType>,
    { ... }
}
Expand description

PostgreSQL specific methods which are present on all expressions.

Provided methods

Creates a PostgreSQL IS NOT DISTINCT FROM expression.

This behaves identically to the = operator, except that NULL is treated as a normal value.

Example
let distinct = users.select(id).filter(name.is_distinct_from("Sean"));
let not_distinct = users.select(id).filter(name.is_not_distinct_from("Sean"));
assert_eq!(Ok(2), distinct.first(&connection));
assert_eq!(Ok(1), not_distinct.first(&connection));

Creates a PostgreSQL IS DISTINCT FROM expression.

This behaves identically to the != operator, except that NULL is treated as a normal value.

Example
let distinct = users.select(id).filter(name.is_distinct_from("Sean"));
let not_distinct = users.select(id).filter(name.is_not_distinct_from("Sean"));
assert_eq!(Ok(2), distinct.first(&connection));
assert_eq!(Ok(1), not_distinct.first(&connection));

Implementors