1DBIx::Class::Manual::ExUasmeprleC(o3n)tributed Perl DocuDmBeInxt:a:tCiloanss::Manual::Example(3)
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NAME

6       DBIx::Class::Manual::Example - Simple CD database example
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DESCRIPTION

9       This tutorial will guide you through the process of setting up and
10       testing a very basic CD database using SQLite, with DBIx::Class::Schema
11       as the database frontend.
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13       The database structure is based on the following rules:
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15         An artist can have many cds, and each cd belongs to just one artist.
16         A cd can have many tracks, and each track belongs to just one cd.
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18       The database is implemented with the following:
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20         table 'artist' with columns:  artistid, name
21         table 'cd'     with columns:  cdid, artistid, title, year
22         table 'track'  with columns:  trackid, cdid, title
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24       Each of the table's first columns is the primary key; any subsequent
25       keys are foreign keys.
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27   Installation
28       You'll need to install DBIx::Class via CPAN, and you'll also need to
29       install sqlite3 (not sqlite) if it's not already intalled.
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31       The database/tables/data
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33       Your distribution already comes with a pre-filled SQLite database
34       examples/Schema/db/example.db. You can see it by e.g.
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36         cpanm --look DBIx::Class
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38       If for some reason the file is unreadable on your system, you can
39       recreate it as follows:
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41         cp -a <unpacked-DBIC-tarball>/examples/Schema dbicapp
42         cd dbicapp
43         rm db/example.db
44         sqlite3 db/example.db < db/example.sql
45         perl insertdb.pl
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47       Testing the database
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49       Enter the example Schema directory
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51         cd <unpacked-DBIC-tarball>/examples/Schema
52
53       Run the script testdb.pl, which will test that the database has
54       successfully been filled.
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56       When this script is run, it should output the following:
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58        get_tracks_by_cd(Bad):
59        Leave Me Alone
60        Smooth Criminal
61        Dirty Diana
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63        get_tracks_by_artist(Michael Jackson):
64        Billie Jean (from the CD 'Thriller')
65        Beat It (from the CD 'Thriller')
66        Leave Me Alone (from the CD 'Bad')
67        Smooth Criminal (from the CD 'Bad')
68        Dirty Diana (from the CD 'Bad')
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70        get_cd_by_track(Stan):
71        The Marshall Mathers LP has the track 'Stan'.
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73        get_cds_by_artist(Michael Jackson):
74        Thriller
75        Bad
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77        get_artist_by_track(Dirty Diana):
78        Michael Jackson recorded the track 'Dirty Diana'.
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80        get_artist_by_cd(The Marshall Mathers LP):
81        Eminem recorded the CD 'The Marshall Mathers LP'.
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83       Discussion about the results
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85       The data model defined in this example has an artist with multiple CDs,
86       and a CD with multiple tracks; thus, it's simple to traverse from a
87       track back to a CD, and from there back to an artist. This is
88       demonstrated in the get_tracks_by_artist routine, where we easily walk
89       from the individual track back to the title of the CD that the track
90       came from ($track->cd->title).
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92       Note also that in the get_tracks_by_cd and get_tracks_by_artist
93       routines, the result set is called multiple times with the 'next'
94       iterator.  In contrast, get_cd_by_track uses the 'first' result set
95       method, since only one CD is expected to have a specific track.
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97       This example uses "load_namespaces" in DBIx::Class::Schema to load in
98       the appropriate Result classes from the "MyApp::Schema::Result"
99       namespace, and any required ResultSet classes from the
100       "MyApp::Schema::ResultSet" namespace (although we did not add, nor
101       needed any such classes in this example).
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FURTHER QUESTIONS?

104       Check the list of additional DBIC resources.
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107       This module is free software copyright by the DBIx::Class (DBIC)
108       authors. You can redistribute it and/or modify it under the same terms
109       as the DBIx::Class library.
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113perl v5.36.0                      2022-07-22   DBIx::Class::Manual::Example(3)
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