1Attean::Plan(3)       User Contributed Perl Documentation      Attean::Plan(3)
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NAME

6       Attean::Plan - Representation of SPARQL query plan operators
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VERSION

9       This document describes Attean::Plan version 0.030
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SYNOPSIS

12         use v5.14;
13         use Attean;
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DESCRIPTION

16       This is a utility package that defines all the Attean query plan
17       classes in the Attean::Plan namespace:
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19       •   Attean::Plan::Quad
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21           Evaluates a quad pattern against the model.
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23       •   Attean::Plan::NestedLoopJoin
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25           Evaluates a join (natural-, anti-, or left-) using a nested loop.
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27       •   Attean::Plan::HashJoin
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29           Evaluates a join (natural-, anti-, or left-) using a hash join.
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31       •   Attean::Plan::Construct
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33       •   Attean::Plan::Describe
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35       •   Attean::Plan::EBVFilter
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37           Filters results from a sub-plan based on the effective boolean
38           value of a named variable binding.
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40       •   Attean::Plan::Merge
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42           Evaluates a set of sub-plans, returning the merged union of
43           results, preserving ordering.
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45       •   Attean::Plan::Union
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47           Evaluates a set of sub-plans, returning the union of results.
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49       •   Attean::Plan::Extend
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51           Evaluates a sub-plan, and extends each result by evaluating a set
52           of expressions, binding the produced values to new variables.
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54       •   Attean::Plan::HashDistinct
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56           Evaluates a sub-plan, and returns distinct results by checking a
57           persistent hash of already-seen results.
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59       •   Attean::Plan::Unique
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61           Evaluates an already-ordered sub-plan, and returns distinct results
62           by filtering out sequential duplicates.
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64       •   Attean::Plan::Slice
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66           Evaluates a sub-plan, and returns the results after optionally
67           skipping some number of results ("offset") and limiting the total
68           number of returned results ("limit").
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70       •   Attean::Plan::Project
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72           Evaluates a sub-plan and returns projected results by only keeping
73           a fixed-set of variable bindings in each result.
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75       •   Attean::Plan::OrderBy
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77           Evaluates a sub-plan and returns the results after fully
78           materializing and sorting is applied.
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80       •   Attean::Plan::Service
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82           Evaluates a SPARQL query against a remote endpoint.
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84       •   Attean::Plan::Table
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86           Returns a constant set of results.
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88       •   Attean::Plan::Iterator
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90           Returns a constant set of results.
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92           Be aware that if the iterator being wrapped is not repeatable
93           (consuming the Attean::API::RepeatableIterator role), then this
94           plan may only be evaluated once.
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96           A size estimate may be given if it is available. If the iterator is
97           an Attean::ListIterator, the size of that iterator will be used.
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99       •   Attean::Plan::ALPPath
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101       •   Attean::Plan::Exists
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103           Returns an iterator containing a single boolean term indicating
104           whether any results were produced by evaluating the sub-plan.
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106       •   Attean::Plan::Aggregate
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BUGS

109       Please report any bugs or feature requests to through the GitHub web
110       interface at <https://github.com/kasei/attean/issues>.
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SEE ALSO

AUTHOR
114       Gregory Todd Williams  "<gwilliams@cpan.org>"
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117       Copyright (c) 2014--2020 Gregory Todd Williams.  This program is free
118       software; you can redistribute it and/or modify it under the same terms
119       as Perl itself.
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123perl v5.32.1                      2021-02-08                   Attean::Plan(3)



        

    


            
        

        

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