Flow PHP

Sum implements AggregatingFunction, FrameAccumulating, WindowFunction uses ResolvesFromChildren

FinalYes

Interfaces

AggregatingFunction
FrameAccumulating: Opts a WindowFunction into incremental frame evaluation. Carrying it asserts the result depends only on the frame contents - never on the current row or its index - which is what lets WindowProcessor reuse a value across rows that share frame bounds.
WindowFunction

Methods

__construct() : mixed
accumulator() : FrameAccumulator
aggregate() : void
apply() : mixed
children() : array<int, FunctionTree>: Every operand of this node that is an expression, in constructor order.
outputName() : string: Decided in the constructor, never mutated.
over() : static: Returns a copy bound to $window. Never mutates $this.
references() : null|array<int, Reference>
resolved() : bool
returns() : Type<string|int, mixed>: float, not the argument type - RunningSum::add() promotes to float on int overflow, so integer would be a declaration the accumulator can violate on ordinary data
toString() : string
value() : null|array<string|int, mixed>|bool|float|int|object|string
window() : Window
withChildren() : static: A copy of this node with $children in place of children(): same count, same order, same per-element narrowing. Never mutates $this.

__construct()


    public
                    __construct(Reference $ref[, ScalarFunction|bool $exact = false ][, Window|null $window = null ]) : mixed

Parameters

$ref : Reference
$exact : ScalarFunction|bool = false
$window : Window|null = null

accumulator()


    public
                    accumulator(FlowContext $context) : FrameAccumulator

Parameters

$context : FlowContext

Return values

FrameAccumulator

aggregate()


    public
                    aggregate(Row $row, FlowContext $context) : void

Parameters

$row : Row
$context : FlowContext

apply()


    public
                    apply(WindowContext $window) : mixed

Parameters

$window : WindowContext

children()

Every operand of this node that is an expression, in constructor order.


    public
                    children() : array<int, FunctionTree>

Return values

array<int, FunctionTree>

outputName()

Decided in the constructor, never mutated.


    public
                    outputName() : string

Return values

string

over()

Returns a copy bound to $window. Never mutates $this.


    public
                    over(Window $window) : static

Parameters

$window : Window

Return values

static

references()


    public
                    references() : null|array<int, Reference>

Return values

null|array<int, Reference> —

null when $exact is a ScalarFunction - its entries cannot be statically enumerated, so spill column pruning must be disabled

resolved()


    public
                    resolved() : bool

Return values

bool

returns()

float, not the argument type - RunningSum::add() promotes to float on int overflow, so integer would be a declaration the accumulator can violate on ordinary data


    public
                    returns() : Type<string|int, mixed>

Return values

Type<string|int, mixed>

toString()


    public
                    toString() : string

Return values

string

value()


    public
                    value() : null|array<string|int, mixed>|bool|float|int|object|string

Return values

window()


    public
                    window() : Window

Return values

Window

withChildren()

A copy of this node with $children in place of children(): same count, same order, same per-element narrowing. Never mutates $this.


    public
                    withChildren(array<int, FunctionTree> $children) : static

Parameters

$children : array<int, FunctionTree>

Return values

static