Struct mz_expr::FilterCharacteristics

pub struct FilterCharacteristics {
    literal_equality: bool,
    like: bool,
    is_null: bool,
    literal_inequality: usize,
    any_filter: bool,
}

Filter characteristics that are used for ordering join inputs. This can be created for a Vec<MirScalarExpr>, which represents an AND of predicates.

The fields are ordered based on heuristic assumptions about their typical selectivity, so that Ord gives the right ordering for join inputs. Bigger is better, i.e., will tend to come earlier than other inputs.

Fields

literal_equality: bool

like: bool

is_null: bool

literal_inequality: usize

any_filter: bool

Any filter, except ones involving IS NOT NULL, because those are too common. Can be true by itself, or any other field being true can also make this true. NOT LIKE is only in this category. != is only in this category. NOT (a = b) is turned into != by reduce before us!

Implementations

impl FilterCharacteristics

pub fn none() -> FilterCharacteristics

pub fn explain(&self) -> String

pub fn filter_characteristics( filters: &Vec<MirScalarExpr>, ) -> Result<FilterCharacteristics, RecursionLimitError>

pub fn add_literal_equality(&mut self)

pub fn worst_case_scaling_factor(&self) -> f64

Trait Implementations

impl Arbitrary for FilterCharacteristics

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

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

type Strategy = Map<(<bool as Arbitrary>::Strategy, <bool as Arbitrary>::Strategy, <bool as Arbitrary>::Strategy, <usize as Arbitrary>::Strategy, <bool as Arbitrary>::Strategy), fn(_: (bool, bool, bool, usize, bool)) -> FilterCharacteristics>

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 BitOrAssign for FilterCharacteristics

fn bitor_assign(&mut self, rhs: Self)

Performs the |= operation.

impl Clone for FilterCharacteristics

fn clone(&self) -> FilterCharacteristics

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for FilterCharacteristics

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for FilterCharacteristics

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for FilterCharacteristics

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 FilterCharacteristics

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 FilterCharacteristics

fn cmp(&self, other: &FilterCharacteristics) -> 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 + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for FilterCharacteristics

fn eq(&self, other: &FilterCharacteristics) -> 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 FilterCharacteristics

fn partial_cmp(&self, other: &FilterCharacteristics) -> 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 Serialize for FilterCharacteristics

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 FilterCharacteristics

impl StructuralPartialEq for FilterCharacteristics