Enum mz_sql::plan::WindowExprType

pub enum WindowExprType {
    Scalar(ScalarWindowExpr),
    Value(ValueWindowExpr),
    Aggregate(AggregateWindowExpr),
}

A window function with its parameters.

There are three types of window functions:

• scalar window functions, which return a different scalar value for each row within a partition that depends exclusively on the position of the row within the partition;
• value window functions, which return a scalar value for each row within a partition that might be computed based on a single row, which is usually not the current row (e.g., previous or following row; first or last row of the partition);
• aggregate window functions, which compute a traditional aggregation as a window function (e.g. sum(x) OVER (...)). (Aggregate window functions can in some cases be computed by joining the input relation with a reduction over the same relation that computes the aggregation using the partition key as its grouping key, but we don’t automatically do this currently.)

Variants

Scalar(ScalarWindowExpr)

Value(ValueWindowExpr)

Aggregate(AggregateWindowExpr)

Implementations

impl WindowExprType

pub fn visit_expressions<'a, F, E>(&'a self, f: &mut F) -> Result<(), E>

where F: FnMut(&'a HirScalarExpr) -> Result<(), E>,

👎Deprecated: Use VisitChildren<HirScalarExpr>::visit_children instead.

pub fn visit_expressions_mut<'a, F, E>(&'a mut self, f: &mut F) -> Result<(), E>

where F: FnMut(&'a mut HirScalarExpr) -> Result<(), E>,

👎Deprecated: Use VisitChildren<HirScalarExpr>::visit_mut_children instead.

fn typ( &self, outers: &[RelationType], inner: &RelationType, params: &BTreeMap<usize, ScalarType>, ) -> ColumnType

Trait Implementations

impl Clone for WindowExprType

fn clone(&self) -> WindowExprType

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for WindowExprType

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for WindowExprType

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for WindowExprType

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 Ord for WindowExprType

fn cmp(&self, other: &WindowExprType) -> 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 WindowExprType

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

fn partial_cmp(&self, other: &WindowExprType) -> 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 WindowExprType

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl VisitChildren<HirScalarExpr> for WindowExprType

fn visit_children<F>(&self, f: F)

where F: FnMut(&HirScalarExpr),

Apply an infallible immutable function f to each direct child.

fn visit_mut_children<F>(&mut self, f: F)

where F: FnMut(&mut HirScalarExpr),

Apply an infallible mutable function f to each direct child.

fn try_visit_children<F, E>(&self, f: F) -> Result<(), E>

where F: FnMut(&HirScalarExpr) -> Result<(), E>, E: From<RecursionLimitError>,

Apply a fallible immutable function f to each direct child.

fn try_visit_mut_children<F, E>(&mut self, f: F) -> Result<(), E>

where F: FnMut(&mut HirScalarExpr) -> Result<(), E>, E: From<RecursionLimitError>,

Apply a fallible mutable function f to each direct child.

impl Eq for WindowExprType

impl StructuralPartialEq for WindowExprType