1DBIx::Class::Helper::ReUssuelrtSCeotn:tD:rBSiIebxtu:Ot:peCedlraaPstesir:ol:nHsDe(ol3cp)uemre:n:tRaetsiuolntSet::SetOperations(3)
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6 DBIx::Class::Helper::ResultSet::SetOperations - Do set operations with
7 DBIx::Class
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10 package MyApp::Schema::ResultSet::Foo;
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12 __PACKAGE__->load_components(qw{Helper::ResultSet::SetOperations});
13
14 ...
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16 1;
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18 And then elsewhere, like in a controller:
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20 my $rs1 = $rs->search({ foo => 'bar' });
21 my $rs2 = $rs->search({ baz => 'biff' });
22 for ($rs1->union($rs2)->all) { ... }
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25 This component allows you to use various set operations with your
26 ResultSets. See "NOTE" in DBIx::Class::Helper::ResultSet for a nice
27 way to apply it to your entire schema.
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29 Component throws exceptions if ResultSets have different ResultClasses
30 or different "Columns Specs."
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32 The basic idea here is that in SQL if you use a set operation they must
33 be selecting the same columns names, so that the results will all
34 match. The deal with the ResultClasses is that DBIC needs to inflate
35 the results the same for the entire ResultSet, so if one were to try to
36 apply something like a union in a table with the same column name but
37 different classes DBIC wouldn't be doing what you would expect.
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39 A nice way to use this is with
40 DBIx::Class::ResultClass::HashRefInflator.
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42 You might have something like the following sketch autocompletion code:
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44 my $rs1 = $schema->resultset('Album')->search({
45 name => { -like => "$input%" }
46 }, {
47 columns => [qw( id name ), {
48 tablename => \['?', [{} => 'album']],
49 }],
50 });
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52 my $rs2 = $schema->resultset('Artist')->search({
53 name => { -like => "$input%" }
54 }, {
55 columns => [qw( id name ), {
56 tablename => \['?', [{} => 'artist']],
57 }],
58 });
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60 my $rs3 = $schema->resultset('Song')->search({
61 name => { -like => "$input%" }
62 }, {
63 columns => [qw( id name ), {
64 tablename => \['?', [{} => 'song']],
65 }],
66 });
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68 $_->result_class('DBIx::Class::ResultClass::HashRefInflator')
69 for ($rs1, $rs2, $rs3);
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71 my $data = [$rs1->union([$rs2, $rs3])->all];
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74 union
75 union_all
76 intersect
77 intersect_all
78 except
79 except_all
80 All of these methods take a single ResultSet or an ArrayRef of
81 ResultSets as the parameter only parameter.
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83 On Oracle "except" will issue a "MINUS" operation.
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86 Arthur Axel "fREW" Schmidt <frioux+cpan@gmail.com>
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89 This software is copyright (c) 2020 by Arthur Axel "fREW" Schmidt.
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91 This is free software; you can redistribute it and/or modify it under
92 the same terms as the Perl 5 programming language system itself.
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96perl v5.34.0 DBIx2:0:2C2l-a0s1s-:2:1Helper::ResultSet::SetOperations(3)