1Attean::Plan(3)       User Contributed Perl Documentation      Attean::Plan(3)
2
3
4

NAME

6       Attean::Plan - Representation of SPARQL query plan operators
7

VERSION

9       This document describes Attean::Plan version 0.030
10

SYNOPSIS

12         use v5.14;
13         use Attean;
14

DESCRIPTION

16       This is a utility package that defines all the Attean query plan
17       classes in the Attean::Plan namespace:
18
19       •   Attean::Plan::Quad
20
21           Evaluates a quad pattern against the model.
22
23       •   Attean::Plan::NestedLoopJoin
24
25           Evaluates a join (natural-, anti-, or left-) using a nested loop.
26
27       •   Attean::Plan::HashJoin
28
29           Evaluates a join (natural-, anti-, or left-) using a hash join.
30
31       •   Attean::Plan::Construct
32
33       •   Attean::Plan::Describe
34
35       •   Attean::Plan::EBVFilter
36
37           Filters results from a sub-plan based on the effective boolean
38           value of a named variable binding.
39
40       •   Attean::Plan::Merge
41
42           Evaluates a set of sub-plans, returning the merged union of
43           results, preserving ordering.
44
45       •   Attean::Plan::Union
46
47           Evaluates a set of sub-plans, returning the union of results.
48
49       •   Attean::Plan::Extend
50
51           Evaluates a sub-plan, and extends each result by evaluating a set
52           of expressions, binding the produced values to new variables.
53
54       •   Attean::Plan::HashDistinct
55
56           Evaluates a sub-plan, and returns distinct results by checking a
57           persistent hash of already-seen results.
58
59       •   Attean::Plan::Unique
60
61           Evaluates an already-ordered sub-plan, and returns distinct results
62           by filtering out sequential duplicates.
63
64       •   Attean::Plan::Slice
65
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").
69
70       •   Attean::Plan::Project
71
72           Evaluates a sub-plan and returns projected results by only keeping
73           a fixed-set of variable bindings in each result.
74
75       •   Attean::Plan::OrderBy
76
77           Evaluates a sub-plan and returns the results after fully
78           materializing and sorting is applied.
79
80       •   Attean::Plan::Service
81
82           Evaluates a SPARQL query against a remote endpoint.
83
84       •   Attean::Plan::Table
85
86           Returns a constant set of results.
87
88       •   Attean::Plan::Iterator
89
90           Returns a constant set of results.
91
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.
95
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.
98
99       •   Attean::Plan::ALPPath
100
101       •   Attean::Plan::Exists
102
103           Returns an iterator containing a single boolean term indicating
104           whether any results were produced by evaluating the sub-plan.
105
106       •   Attean::Plan::Aggregate
107

BUGS

109       Please report any bugs or feature requests to through the GitHub web
110       interface at <https://github.com/kasei/attean/issues>.
111

SEE ALSO

AUTHOR

114       Gregory Todd Williams  "<gwilliams@cpan.org>"
115
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.
120
121
122
123perl v5.32.1                      2021-02-08                   Attean::Plan(3)
Impressum