Struct RelationType

pub struct RelationType {
    pub column_types: Vec<ColumnType>,
    pub keys: Vec<Vec<usize>>,
}

The type of a relation.

Fields

column_types: Vec<ColumnType>

The type for each column, in order.

keys: Vec<Vec<usize>>

Sets of indices that are “keys” for the collection.

Each element in this list is a set of column indices, each with the property that the collection contains at most one record with each distinct set of values for each column. Alternately, for a specific set of values assigned to the these columns there is at most one record.

A collection can contain multiple sets of keys, although it is common to have either zero or one sets of key indices.

Implementations

impl RelationType

pub fn empty() -> Self

Constructs a RelationType representing the relation with no columns and no keys.

pub fn new(column_types: Vec<ColumnType>) -> Self

Constructs a new RelationType from specified column types.

The RelationType will have no keys.

pub fn with_key(self, indices: Vec<usize>) -> Self

Adds a new key for the relation.

pub fn with_keys(self, keys: Vec<Vec<usize>>) -> Self

pub fn arity(&self) -> usize

Computes the number of columns in the relation.

pub fn default_key(&self) -> Vec<usize>

Gets the index of the columns used when creating a default index.

pub fn columns(&self) -> &[ColumnType]

Returns all the ColumnTypes, in order, for this relation.

Trait Implementations

impl Arbitrary for RelationType

type Parameters = (<Vec<ColumnType> as Arbitrary>::Parameters, <Vec<Vec<usize>> as Arbitrary>::Parameters)

The type of parameters that arbitrary_with accepts for configuration of the generated Strategy. Parameters must implement Default.

type Strategy = Map<(<Vec<ColumnType> as Arbitrary>::Strategy, <Vec<Vec<usize>> as Arbitrary>::Strategy), fn((Vec<ColumnType>, Vec<Vec<usize>>)) -> RelationType>

The type of Strategy used to generate values of type Self.

fn arbitrary_with(_top: Self::Parameters) -> Self::Strategy

Generates a Strategy for producing arbitrary values of type the implementing type (Self). The strategy is passed the arguments given in args.

fn arbitrary() -> Self::Strategy

Generates a Strategy for producing arbitrary values of type the implementing type (Self).

impl Clone for RelationType

fn clone(&self) -> RelationType

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for RelationType

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for RelationType

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for RelationType

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl MzReflect for RelationType

fn add_to_reflected_type_info(rti: &mut ReflectedTypeInfo)

Adds names and types of the fields of the struct or enum to rti.

impl Ord for RelationType

fn cmp(&self, other: &RelationType) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for RelationType

fn eq(&self, other: &RelationType) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for RelationType

fn partial_cmp(&self, other: &RelationType) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl RustType<ProtoRelationType> for RelationType

fn into_proto(&self) -> ProtoRelationType

Convert a Self into a Proto value.

fn from_proto(proto: ProtoRelationType) -> Result<Self, TryFromProtoError>

Consume and convert a Proto back into a Self value.

fn into_proto_owned(self) -> Proto

A zero clone version of Self::into_proto that types can optionally implement, otherwise, the default implementation delegates to Self::into_proto.

impl Serialize for RelationType

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for RelationType

impl StructuralPartialEq for RelationType