Module datafusion::physical_plan::functions

Declaration of built-in (scalar) functions. This module contains built-in functions’ enumeration and metadata.

Generally, a function has:

• a signature

• a return type, that is a function of the incoming argument’s types

• the computation, that must accept each valid signature

• Signature: see Signature

• Return type: a function (arg_types) -> return_type. E.g. for sqrt, (f32) -> f32, (f64) -> f64.

This module also has a set of coercion rules to improve user experience: if an argument i32 is passed to a function that supports f64, it is coerced to f64.

Structs

ScalarFunctionExpr

Physical expression of a scalar function

Enums

BuiltinScalarFunction	Enum of all built-in scalar functions
Signature	A function’s signature, which defines the function’s supported argument types.

Functions

create_physical_expr	Create a physical (function) expression. This function errors when args’ can’t be coerced to a valid argument type of the function.
make_scalar_function	decorates a function to handle ScalarValues by coverting them to arrays before calling the function and vice-versa after evaluation.
return_type	Returns the datatype of the scalar function

Type Definitions

ReturnTypeFunction	A function’s return type
ScalarFunctionImplementation	Scalar function