Struct mz_expr::AggregateExpr

pub struct AggregateExpr {
    pub func: AggregateFunc,
    pub expr: MirScalarExpr,
    pub distinct: bool,
}

Describes an aggregation expression.

Fields

func: AggregateFunc

Names the aggregation function.

expr: MirScalarExpr

An expression which extracts from each row the input to func.

distinct: bool

Should the aggregation be applied only to distinct results in each group.

Implementations

impl AggregateExpr

pub fn typ(&self, column_types: &[ColumnType]) -> ColumnType

Computes the type of this AggregateExpr.

pub fn is_constant(&self) -> bool

Returns whether the expression has a constant result.

pub fn on_unique(&self, input_type: &[ColumnType]) -> MirScalarExpr

Extracts unique input from aggregate type

pub fn is_count_asterisk(&self) -> bool

Returns whether the expression is COUNT() or not. Note that when we define the count builtin in sql::func, we convert COUNT() to COUNT(true), making it indistinguishable from literal COUNT(true), but we prefer to consider this as the former.

Trait Implementations

impl Arbitrary for AggregateExpr

type Parameters = (<AggregateFunc as Arbitrary>::Parameters, <MirScalarExpr 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<(<AggregateFunc as Arbitrary>::Strategy, <MirScalarExpr as Arbitrary>::Strategy, <bool as Arbitrary>::Strategy), fn(_: (AggregateFunc, MirScalarExpr, bool)) -> AggregateExpr>

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 AggregateExpr

fn clone(&self) -> AggregateExpr

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for AggregateExpr

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for AggregateExpr

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>where
    __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for AggregateExpr

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

Formats the value using the given formatter.

impl DisplayText<()> for AggregateExpr

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

impl Hash for AggregateExpr

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 AggregateExpr

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 AggregateExpr

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

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere
    Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl PartialEq<AggregateExpr> for AggregateExpr

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

This method tests for self and other values to be equal, and is used by ==.

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

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

impl PartialOrd<AggregateExpr> for AggregateExpr

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

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

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

This method tests less than (for self and other) and is used by the < operator.

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

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

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

This method tests greater than (for self and other) and is used by the > operator.

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

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

impl RustType<ProtoAggregateExpr> for AggregateExpr

fn into_proto(&self) -> ProtoAggregateExpr

Convert a Self into a Proto value.

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

Consume and convert a Proto back into a Self value.

impl Serialize for AggregateExpr

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 AggregateExpr

impl StructuralEq for AggregateExpr

impl StructuralPartialEq for AggregateExpr