Module windows 

Physical expressions for window functions

Modules

bounded_window_agg_exec 🔒

Stream and channel implementations for window function expressions. The executor given here uses bounded memory (does not maintain all the input data seen so far), which makes it appropriate when processing infinite inputs.

utils 🔒

window_agg_exec 🔒

Stream and channel implementations for window function expressions.

Structs

BoundedWindowAggExec

Window execution plan

PlainAggregateWindowExpr

A window expr that takes the form of an aggregate function.

StandardWindowExpr

A window expr that takes the form of a [StandardWindowFunctionExpr].

WindowAggExec

Window execution plan

WindowUDFExpr

Implements [StandardWindowFunctionExpr] for WindowUDF

Traits

WindowExpr

Common trait for window function implementations

Functions

calc_requirements 🔒

create_udwf_window_expr

Creates a StandardWindowFunctionExpr suitable for a user defined window function

create_window_expr

Create a physical expression for window function

get_best_fitting_window

Constructs the best-fitting windowing operator (a WindowAggExec or a BoundedWindowExec) for the given input according to the specifications of window_exprs and physical_partition_keys. Here, best-fitting means not requiring additional sorting and/or partitioning for the given input.

get_ordered_partition_by_indices

This function calculates the indices such that when partition by expressions reordered with the indices resulting expressions define a preset for existing ordering. For instance, if input is ordered by a, b, c and PARTITION BY b, a is used, this vector will be [1, 0]. It means that when we iterate b, a columns with the order [1, 0] resulting vector (a, b) is a preset of the existing ordering (a, b, c).

get_partition_by_sort_exprs 🔒

get_window_mode

Compares physical ordering (output ordering of the input operator) with partitionby_exprs and orderby_keys to decide whether existing ordering is sufficient to run the current window operator.

schema_add_window_field

Build field from window function and add it into schema

sort_options_resolving_constant 🔒

Generates sort option variations for a given expression.

window_equivalence_properties 🔒

window_expr_from_aggregate_expr 🔒

Creates an appropriate WindowExpr based on the window frame and