Trait datafusion_physical_expr::PhysicalExpr

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pub trait PhysicalExpr: Send + Sync + Display + Debug + PartialEq<dyn Any> {
    // Required methods
    fn as_any(&self) -> &dyn Any;
    fn data_type(&self, input_schema: &Schema) -> Result<DataType>;
    fn nullable(&self, input_schema: &Schema) -> Result<bool>;
    fn evaluate(&self, batch: &RecordBatch) -> Result<ColumnarValue>;
    fn children(&self) -> Vec<Arc<dyn PhysicalExpr>> ⓘ;
    fn with_new_children(
        self: Arc<Self>,
        children: Vec<Arc<dyn PhysicalExpr>>
    ) -> Result<Arc<dyn PhysicalExpr>>;

    // Provided methods
    fn evaluate_selection(
        &self,
        batch: &RecordBatch,
        selection: &BooleanArray
    ) -> Result<ColumnarValue> { ... }
    fn analyze(&self, context: AnalysisContext) -> AnalysisContext { ... }
    fn evaluate_bounds(&self, _children: &[&Interval]) -> Result<Interval> { ... }
    fn propagate_constraints(
        &self,
        _interval: &Interval,
        _children: &[&Interval]
    ) -> Result<Vec<Option<Interval>>> { ... }
}
Expand description

Expression that can be evaluated against a RecordBatch A Physical expression knows its type, nullability and how to evaluate itself.

Required Methods§

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fn as_any(&self) -> &dyn Any

Returns the physical expression as Any so that it can be downcast to a specific implementation.

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fn data_type(&self, input_schema: &Schema) -> Result<DataType>

Get the data type of this expression, given the schema of the input

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fn nullable(&self, input_schema: &Schema) -> Result<bool>

Determine whether this expression is nullable, given the schema of the input

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fn evaluate(&self, batch: &RecordBatch) -> Result<ColumnarValue>

Evaluate an expression against a RecordBatch

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fn children(&self) -> Vec<Arc<dyn PhysicalExpr>> ⓘ

Get a list of child PhysicalExpr that provide the input for this expr.

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fn with_new_children( self: Arc<Self>, children: Vec<Arc<dyn PhysicalExpr>> ) -> Result<Arc<dyn PhysicalExpr>>

Returns a new PhysicalExpr where all children were replaced by new exprs.

Provided Methods§

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fn evaluate_selection( &self, batch: &RecordBatch, selection: &BooleanArray ) -> Result<ColumnarValue>

Evaluate an expression against a RecordBatch after first applying a validity array

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fn analyze(&self, context: AnalysisContext) -> AnalysisContext

Return the boundaries of this expression. This method (and all the related APIs) are experimental and subject to change.

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fn evaluate_bounds(&self, _children: &[&Interval]) -> Result<Interval>

Computes bounds for the expression using interval arithmetic.

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fn propagate_constraints( &self, _interval: &Interval, _children: &[&Interval] ) -> Result<Vec<Option<Interval>>>

Updates/shrinks bounds for the expression using interval arithmetic. If constraint propagation reveals an infeasibility, returns None for the child causing infeasibility. If none of the children intervals change, may return an empty vector instead of cloning children.

Implementors§