Struct SimpleScalarUDF

pub struct SimpleScalarUDF { /* private fields */ }

Implements ScalarUDFImpl for functions that have a single signature and return type.

Implementations

impl SimpleScalarUDF

pub fn new( name: impl Into<String>, input_types: Vec<DataType>, return_type: DataType, volatility: Volatility, fun: Arc<dyn Fn(&[ColumnarValue]) -> Result<ColumnarValue, DataFusionError> + Send + Sync>, ) -> SimpleScalarUDF

Create a new SimpleScalarUDF from a name, input types, return type and implementation. Implementing ScalarUDFImpl allows more flexibility

pub fn new_with_signature( name: impl Into<String>, signature: Signature, return_type: DataType, fun: Arc<dyn Fn(&[ColumnarValue]) -> Result<ColumnarValue, DataFusionError> + Send + Sync>, ) -> SimpleScalarUDF

Create a new SimpleScalarUDF from a name, signature, return type and implementation. Implementing ScalarUDFImpl allows more flexibility

Trait Implementations

impl Debug for SimpleScalarUDF

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

Formats the value using the given formatter.

impl ScalarUDFImpl for SimpleScalarUDF

fn as_any(&self) -> &(dyn Any + 'static)

Returns this object as an Any trait object

fn name(&self) -> &str

Returns this function’s name

fn signature(&self) -> &Signature

Returns the function’s Signature for information about what input types are accepted and the function’s Volatility.

fn return_type( &self, _arg_types: &[DataType], ) -> Result<DataType, DataFusionError>

What DataType will be returned by this function, given the types of the arguments.

fn invoke_with_args( &self, args: ScalarFunctionArgs<'_>, ) -> Result<ColumnarValue, DataFusionError>

Invoke the function returning the appropriate result.

fn display_name(&self, args: &[Expr]) -> Result<String, DataFusionError>

Returns the user-defined display name of function, given the arguments

fn schema_name(&self, args: &[Expr]) -> Result<String, DataFusionError>

Returns the name of the column this expression would create

fn return_type_from_args( &self, args: ReturnTypeArgs<'_>, ) -> Result<ReturnInfo, DataFusionError>

What type will be returned by this function, given the arguments?

fn is_nullable(&self, _args: &[Expr], _schema: &dyn ExprSchema) -> bool

👎Deprecated since 45.0.0: Use return_type_from_args instead. if you use is_nullable that returns non-nullable with return_type, you would need to switch to return_type_from_args, you might have error

fn aliases(&self) -> &[String]

Returns any aliases (alternate names) for this function.

fn simplify( &self, args: Vec<Expr>, _info: &dyn SimplifyInfo, ) -> Result<ExprSimplifyResult, DataFusionError>

Optionally apply per-UDF simplification / rewrite rules.

fn short_circuits(&self) -> bool

Returns true if some of this exprs subexpressions may not be evaluated and thus any side effects (like divide by zero) may not be encountered Setting this to true prevents certain optimizations such as common subexpression elimination

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

Computes the output interval for a ScalarUDFImpl, given the input intervals.

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

Updates bounds for child expressions, given a known interval for this function. This is used to propagate constraints down through an expression tree.

fn output_ordering( &self, inputs: &[ExprProperties], ) -> Result<SortProperties, DataFusionError>

Calculates the SortProperties of this function based on its children’s properties.

fn preserves_lex_ordering( &self, _inputs: &[ExprProperties], ) -> Result<bool, DataFusionError>

Whether the function preserves lexicographical ordering based on the input ordering

fn coerce_types( &self, _arg_types: &[DataType], ) -> Result<Vec<DataType>, DataFusionError>

Coerce arguments of a function call to types that the function can evaluate.

fn equals(&self, other: &dyn ScalarUDFImpl) -> bool

Return true if this scalar UDF is equal to the other.

fn hash_value(&self) -> u64

Returns a hash value for this scalar UDF.

fn documentation(&self) -> Option<&Documentation>

Returns the documentation for this Scalar UDF.