Attean::Plan3pm

Usage

  use v5.14;
  use Attean;

Version

This document describes Attean::Plan version 0.035

Overview

This is a utility package that defines all the Attean query plan classes in the Attean::Plan namespace:

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Attean::Plan::Quad

Evaluates a quad pattern against the model.

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Attean::Plan::NestedLoopJoin

Evaluates a join (natural-, anti-, or left-) using a nested loop.

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Attean::Plan::HashJoin

Evaluates a join (natural-, anti-, or left-) using a hash join.

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Attean::Plan::Construct

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Attean::Plan::Describe

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Attean::Plan::EBVFilter

Filters results from a sub-plan based on the effective boolean value of a named variable binding.

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Attean::Plan::Merge

Evaluates a set of sub-plans, returning the merged union of results, preserving ordering.

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Attean::Plan::Union

Evaluates a set of sub-plans, returning the union of results.

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Attean::Plan::Extend

Evaluates a sub-plan, and extends each result by evaluating a set of expressions, binding the produced values to new variables.

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Attean::Plan::HashDistinct

Evaluates a sub-plan, and returns distinct results by checking a persistent hash of already-seen results.

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Attean::Plan::Unique

Evaluates an already-ordered sub-plan, and returns distinct results by filtering out sequential duplicates.

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Attean::Plan::Slice

Evaluates a sub-plan, and returns the results after optionally skipping some number of results ("offset") and limiting the total number of returned results ("limit").

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Attean::Plan::Project

Evaluates a sub-plan and returns projected results by only keeping a fixed-set of variable bindings in each result.

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Attean::Plan::OrderBy

Evaluates a sub-plan and returns the results after fully materializing and sorting is applied.

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Attean::Plan::Service

Evaluates a SPARQL query against a remote endpoint.

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Attean::Plan::Table

Returns a constant set of results.

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Attean::Plan::Iterator

Returns a constant set of results.

Be aware that if the iterator being wrapped is not repeatable (consuming the Attean::API::RepeatableIterator role), then this plan may only be evaluated once.

A size estimate may be given if it is available. If the iterator is an Attean::ListIterator, the size of that iterator will be used.

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Attean::Plan::ALPPath

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Attean::Plan::Exists

Returns an iterator containing a single boolean term indicating whether any results were produced by evaluating the sub-plan.

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Attean::Plan::Aggregate

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Attean::Plan::Unfold