Trait diesel::expression_methods::BoolExpressionMethods [−][src]
pub trait BoolExpressionMethods: Expression<SqlType = Bool> + Sized { fn and<T: AsExpression<Bool>>(self, other: T) -> And<Self, T::Expression> { ... } fn or<T: AsExpression<Bool>>(
self,
other: T
) -> Grouped<Or<Self, T::Expression>> { ... } }
Expand description
Methods present on boolean expressions
Provided methods
fn and<T: AsExpression<Bool>>(self, other: T) -> And<Self, T::Expression>
fn and<T: AsExpression<Bool>>(self, other: T) -> And<Self, T::Expression>
Creates a SQL AND
expression
Example
diesel::insert_into(animals) .values(&vec![ (species.eq("ferret"), legs.eq(4), name.eq("Freddy")), (species.eq("ferret"), legs.eq(4), name.eq("Jack")), ]) .execute(&connection)?; let data = animals.select((species, name)) .filter(species.eq("ferret").and(name.eq("Jack"))) .load(&connection)?; let expected = vec![ (String::from("ferret"), Some(String::from("Jack"))), ]; assert_eq!(expected, data);
fn or<T: AsExpression<Bool>>(self, other: T) -> Grouped<Or<Self, T::Expression>>
fn or<T: AsExpression<Bool>>(self, other: T) -> Grouped<Or<Self, T::Expression>>
Creates a SQL OR
expression
The result will be wrapped in parenthesis, so that precedence matches
that of your function calls. For example, false.and(false.or(true))
will generate the SQL FALSE AND (FALSE OR TRUE)
, which returns false
Example
diesel::insert_into(animals) .values(&vec![ (species.eq("ferret"), legs.eq(4), name.eq("Freddy")), (species.eq("ferret"), legs.eq(4), name.eq("Jack")), ]) .execute(&connection)?; let data = animals.select((species, name)) .filter(species.eq("ferret").or(name.eq("Jack"))) .load(&connection)?; let expected = vec![ (String::from("dog"), Some(String::from("Jack"))), (String::from("ferret"), Some(String::from("Freddy"))), (String::from("ferret"), Some(String::from("Jack"))), ]; assert_eq!(expected, data);