Module projection 

ProjectionExpr and ProjectionExprs for representing projections.

Structs

ProjectionExpr

An expression used by projection operations.

ProjectionExprs

A collection of ProjectionExpr instances, representing a complete projection operation.

ProjectionMapping

Stores the mapping between source expressions and target expressions for a projection.

ProjectionTargets

Stores target expressions, along with their indices, that associate with a source expression in a projection mapping.

Projector

Applies a projection to record batches.

Functions

project_ordering

Projects a single LexOrdering onto the given schema.

project_orderings

Projects a slice of LexOrderings onto the given schema.

update_expr

The function operates in two modes: