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55e2d745 |
1 | package DBIx::Class::Relationship::Base; |
2 | |
3 | use strict; |
4 | use warnings; |
5 | |
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6 | use base qw/DBIx::Class/; |
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7 | |
8 | use Scalar::Util qw/weaken blessed/; |
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9 | use Try::Tiny; |
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10 | use namespace::clean; |
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11 | |
75d07914 |
12 | =head1 NAME |
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13 | |
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14 | DBIx::Class::Relationship::Base - Inter-table relationships |
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15 | |
16 | =head1 SYNOPSIS |
17 | |
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18 | __PACKAGE__->add_relationship( |
19 | spiders => 'My::DB::Result::Creatures', |
20 | sub { |
21 | my $args = shift; |
22 | return { |
23 | "$args->{foreign_alias}.id" => { -ident => "$args->{self_alias}.id" }, |
24 | "$args->{foreign_alias}.type" => 'arachnid' |
25 | }; |
26 | }, |
27 | ); |
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28 | |
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29 | =head1 DESCRIPTION |
30 | |
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31 | This class provides methods to describe the relationships between the |
32 | tables in your database model. These are the "bare bones" relationships |
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33 | methods, for predefined ones, look in L<DBIx::Class::Relationship>. |
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34 | |
35 | =head1 METHODS |
36 | |
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37 | =head2 add_relationship |
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38 | |
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39 | =over 4 |
40 | |
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41 | =item Arguments: 'relname', 'Foreign::Class', $condition, $attrs |
27f01d1f |
42 | |
43 | =back |
30236e47 |
44 | |
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45 | __PACKAGE__->add_relationship('relname', |
46 | 'Foreign::Class', |
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47 | $condition, $attrs); |
48 | |
49 | Create a custom relationship between one result source and another |
50 | source, indicated by its class name. |
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51 | |
406734bb |
52 | =head3 condition |
53 | |
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54 | The condition argument describes the C<ON> clause of the C<JOIN> |
55 | expression used to connect the two sources when creating SQL queries. |
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56 | |
5d2588cc |
57 | =head4 Simple equality |
58 | |
59 | To create simple equality joins, supply a hashref containing the remote |
60 | table column name as the key(s) prefixed by C<'foreign.'>, and the |
61 | corresponding local table column name as the value(s) prefixed by C<'self.'>. |
62 | Both C<foreign> and C<self> are pseudo aliases and must be entered |
63 | literally. They will be replaced with the actual correct table alias |
64 | when the SQL is produced. |
65 | |
66 | For example given: |
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67 | |
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68 | My::Schema::Author->has_many( |
69 | books => 'My::Schema::Book', |
70 | { 'foreign.author_id' => 'self.id' } |
71 | ); |
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72 | |
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73 | A query like: |
74 | |
75 | $author_rs->search_related('books')->next |
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76 | |
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77 | will result in the following C<JOIN> clause: |
78 | |
79 | ... FROM author me LEFT JOIN book books ON books.author_id = me.id ... |
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80 | |
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81 | This describes a relationship between the C<Author> table and the |
82 | C<Book> table where the C<Book> table has a column C<author_id> |
83 | containing the ID value of the C<Author>. |
84 | |
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85 | Similarly: |
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86 | |
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87 | My::Schema::Book->has_many( |
88 | editions => 'My::Schema::Edition', |
89 | { |
90 | 'foreign.publisher_id' => 'self.publisher_id', |
91 | 'foreign.type_id' => 'self.type_id', |
92 | } |
93 | ); |
94 | |
95 | ... |
96 | |
97 | $book_rs->search_related('editions')->next |
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98 | |
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99 | will result in the C<JOIN> clause: |
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100 | |
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101 | ... FROM book me |
102 | LEFT JOIN edition editions ON |
103 | editions.publisher_id = me.publisher_id |
104 | AND editions.type_id = me.type_id ... |
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105 | |
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106 | This describes the relationship from C<Book> to C<Edition>, where the |
107 | C<Edition> table refers to a publisher and a type (e.g. "paperback"): |
108 | |
5d2588cc |
109 | =head4 Multiple groups of simple equality conditions |
110 | |
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111 | As is the default in L<SQL::Abstract>, the key-value pairs will be |
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112 | C<AND>ed in the resulting C<JOIN> clause. An C<OR> can be achieved with |
113 | an arrayref. For example a condition like: |
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114 | |
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115 | My::Schema::Item->has_many( |
116 | related_item_links => My::Schema::Item::Links, |
117 | [ |
118 | { 'foreign.left_itemid' => 'self.id' }, |
119 | { 'foreign.right_itemid' => 'self.id' }, |
120 | ], |
121 | ); |
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122 | |
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123 | will translate to the following C<JOIN> clause: |
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124 | |
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125 | ... FROM item me JOIN item_relations related_item_links ON |
126 | related_item_links.left_itemid = me.id |
127 | OR related_item_links.right_itemid = me.id ... |
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128 | |
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129 | This describes the relationship from C<Item> to C<Item::Links>, where |
130 | C<Item::Links> is a many-to-many linking table, linking items back to |
131 | themselves in a peer fashion (without a "parent-child" designation) |
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132 | |
84d8c2ad |
133 | =head4 Custom join conditions |
134 | |
5d2588cc |
135 | NOTE: The custom join condition specification mechanism is capable of |
136 | generating JOIN clauses of virtually unlimited complexity. This may limit |
137 | your ability to traverse some of the more involved relationship chains the |
138 | way you expect, *and* may bring your RDBMS to its knees. Exercise care |
139 | when declaring relationships as described here. |
140 | |
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141 | To specify joins which describe more than a simple equality of column |
142 | values, the custom join condition coderef syntax can be used. For |
143 | example: |
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144 | |
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145 | My::Schema::Artist->has_many( |
146 | cds_80s => 'My::Schema::CD', |
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147 | sub { |
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148 | my $args = shift; |
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149 | |
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150 | return { |
151 | "$args->{foreign_alias}.artist" => { -ident => "$args->{self_alias}.artistid" }, |
152 | "$args->{foreign_alias}.year" => { '>', "1979", '<', "1990" }, |
153 | }; |
154 | } |
155 | ); |
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156 | |
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157 | ... |
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158 | |
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159 | $artist_rs->search_related('cds_80s')->next; |
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160 | |
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161 | will result in the C<JOIN> clause: |
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162 | |
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163 | ... FROM artist me LEFT JOIN cd cds_80s ON |
164 | cds_80s.artist = me.artistid |
165 | AND cds_80s.year < ? |
166 | AND cds_80s.year > ? |
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167 | |
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168 | with the bind values: |
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169 | |
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170 | '1990', '1979' |
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171 | |
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172 | C<< $args->{foreign_alias} >> and C<< $args->{self_alias} >> are supplied the |
173 | same values that would be otherwise substituted for C<foreign> and C<self> |
174 | in the simple hashref syntax case. |
175 | |
176 | The coderef is expected to return a valid L<SQL::Abstract> query-structure, just |
177 | like what one would supply as the first argument to |
178 | L<DBIx::Class::ResultSet/search>. The return value will be passed directly to |
179 | L<SQL::Abstract> and the resulting SQL will be used verbatim as the C<ON> |
180 | clause of the C<JOIN> statement associated with this relationship. |
181 | |
182 | While every coderef-based condition must return a valid C<ON> clause, it may |
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183 | elect to additionally return a simplified join-free condition hashref when |
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184 | invoked as C<< $result->relationship >>, as opposed to |
185 | C<< $rs->related_resultset('relationship') >>. In this case C<$result> is |
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186 | passed to the coderef as C<< $args->{self_rowobj} >>, so a user can do the |
187 | following: |
188 | |
189 | sub { |
190 | my $args = shift; |
191 | |
192 | return ( |
193 | { |
194 | "$args->{foreign_alias}.artist" => { -ident => "$args->{self_alias}.artistid" }, |
195 | "$args->{foreign_alias}.year" => { '>', "1979", '<', "1990" }, |
196 | }, |
197 | $args->{self_rowobj} && { |
198 | "$args->{foreign_alias}.artist" => $args->{self_rowobj}->artistid, |
199 | "$args->{foreign_alias}.year" => { '>', "1979", '<', "1990" }, |
200 | }, |
201 | ); |
13523f29 |
202 | } |
203 | |
204 | Now this code: |
205 | |
206 | my $artist = $schema->resultset("Artist")->find({ id => 4 }); |
207 | $artist->cds_80s->all; |
208 | |
6c4f4d69 |
209 | Can skip a C<JOIN> altogether and instead produce: |
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210 | |
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211 | SELECT cds_80s.cdid, cds_80s.artist, cds_80s.title, cds_80s.year, cds_80s.genreid, cds_80s.single_track |
212 | FROM cd cds_80s |
213 | WHERE cds_80s.artist = ? |
214 | AND cds_80s.year < ? |
215 | AND cds_80s.year > ? |
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216 | |
217 | With the bind values: |
218 | |
219 | '4', '1990', '1979' |
220 | |
6c4f4d69 |
221 | Note that in order to be able to use |
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222 | L<< $result->create_related|DBIx::Class::Relationship::Base/create_related >>, |
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223 | the coderef must not only return as its second such a "simple" condition |
224 | hashref which does not depend on joins being available, but the hashref must |
225 | contain only plain values/deflatable objects, such that the result can be |
226 | passed directly to L<DBIx::Class::Relationship::Base/set_from_related>. For |
227 | instance the C<year> constraint in the above example prevents the relationship |
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228 | from being used to create related objects (an exception will be thrown). |
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229 | |
230 | In order to allow the user to go truly crazy when generating a custom C<ON> |
231 | clause, the C<$args> hashref passed to the subroutine contains some extra |
232 | metadata. Currently the supplied coderef is executed as: |
233 | |
234 | $relationship_info->{cond}->({ |
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235 | self_alias => The alias of the invoking resultset ('me' in case of a result object), |
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236 | foreign_alias => The alias of the to-be-joined resultset (often matches relname), |
237 | self_resultsource => The invocant's resultsource, |
238 | foreign_relname => The relationship name (does *not* always match foreign_alias), |
dad42de6 |
239 | self_rowobj => The invocant itself in case of a $result_object->$relationship call |
6c4f4d69 |
240 | }); |
8091aa91 |
241 | |
406734bb |
242 | =head3 attributes |
243 | |
244 | The L<standard ResultSet attributes|DBIx::Class::ResultSet/ATTRIBUTES> may |
245 | be used as relationship attributes. In particular, the 'where' attribute is |
246 | useful for filtering relationships: |
247 | |
248 | __PACKAGE__->has_many( 'valid_users', 'MyApp::Schema::User', |
249 | { 'foreign.user_id' => 'self.user_id' }, |
250 | { where => { valid => 1 } } |
251 | ); |
252 | |
253 | The following attributes are also valid: |
8091aa91 |
254 | |
255 | =over 4 |
256 | |
257 | =item join_type |
258 | |
259 | Explicitly specifies the type of join to use in the relationship. Any SQL |
260 | join type is valid, e.g. C<LEFT> or C<RIGHT>. It will be placed in the SQL |
261 | command immediately before C<JOIN>. |
262 | |
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263 | =item proxy =E<gt> $column | \@columns | \%column |
264 | |
9ab122aa |
265 | The 'proxy' attribute can be used to retrieve values, and to perform |
266 | updates if the relationship has 'cascade_update' set. The 'might_have' |
267 | and 'has_one' relationships have this set by default; if you want a proxy |
268 | to update across a 'belongs_to' relationship, you must set the attribute |
269 | yourself. |
270 | |
97c96475 |
271 | =over 4 |
272 | |
273 | =item \@columns |
8091aa91 |
274 | |
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275 | An arrayref containing a list of accessors in the foreign class to create in |
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276 | the main class. If, for example, you do the following: |
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277 | |
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278 | MyApp::Schema::CD->might_have(liner_notes => 'MyApp::Schema::LinerNotes', |
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279 | undef, { |
280 | proxy => [ qw/notes/ ], |
281 | }); |
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282 | |
03460bef |
283 | Then, assuming MyApp::Schema::LinerNotes has an accessor named notes, you can do: |
8091aa91 |
284 | |
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285 | my $cd = MyApp::Schema::CD->find(1); |
30236e47 |
286 | $cd->notes('Notes go here'); # set notes -- LinerNotes object is |
287 | # created if it doesn't exist |
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288 | |
9ab122aa |
289 | For a 'belongs_to relationship, note the 'cascade_update': |
290 | |
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291 | MyApp::Schema::Track->belongs_to( cd => 'MyApp::Schema::CD', 'cd, |
9ab122aa |
292 | { proxy => ['title'], cascade_update => 1 } |
293 | ); |
294 | $track->title('New Title'); |
295 | $track->update; # updates title in CD |
296 | |
97c96475 |
297 | =item \%column |
298 | |
299 | A hashref where each key is the accessor you want installed in the main class, |
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300 | and its value is the name of the original in the foreign class. |
97c96475 |
301 | |
a5fc4975 |
302 | MyApp::Schema::Track->belongs_to( cd => 'MyApp::Schema::CD', 'cd', { |
97c96475 |
303 | proxy => { cd_title => 'title' }, |
304 | }); |
305 | |
dad42de6 |
306 | This will create an accessor named C<cd_title> on the C<$track> result object. |
97c96475 |
307 | |
308 | =back |
309 | |
310 | NOTE: you can pass a nested struct too, for example: |
311 | |
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312 | MyApp::Schema::Track->belongs_to( cd => 'MyApp::Schema::CD', 'cd', { |
97c96475 |
313 | proxy => [ 'year', { cd_title => 'title' } ], |
314 | }); |
315 | |
8091aa91 |
316 | =item accessor |
317 | |
318 | Specifies the type of accessor that should be created for the relationship. |
319 | Valid values are C<single> (for when there is only a single related object), |
320 | C<multi> (when there can be many), and C<filter> (for when there is a single |
321 | related object, but you also want the relationship accessor to double as |
322 | a column accessor). For C<multi> accessors, an add_to_* method is also |
323 | created, which calls C<create_related> for the relationship. |
324 | |
3d618782 |
325 | =item is_foreign_key_constraint |
326 | |
327 | If you are using L<SQL::Translator> to create SQL for you and you find that it |
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328 | is creating constraints where it shouldn't, or not creating them where it |
3d618782 |
329 | should, set this attribute to a true or false value to override the detection |
330 | of when to create constraints. |
331 | |
5f7ac523 |
332 | =item cascade_copy |
333 | |
334 | If C<cascade_copy> is true on a C<has_many> relationship for an |
335 | object, then when you copy the object all the related objects will |
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336 | be copied too. To turn this behaviour off, pass C<< cascade_copy => 0 >> |
337 | in the C<$attr> hashref. |
b7bbc39f |
338 | |
339 | The behaviour defaults to C<< cascade_copy => 1 >> for C<has_many> |
340 | relationships. |
5f7ac523 |
341 | |
342 | =item cascade_delete |
343 | |
b7bbc39f |
344 | By default, DBIx::Class cascades deletes across C<has_many>, |
345 | C<has_one> and C<might_have> relationships. You can disable this |
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346 | behaviour on a per-relationship basis by supplying |
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347 | C<< cascade_delete => 0 >> in the relationship attributes. |
5f7ac523 |
348 | |
349 | The cascaded operations are performed after the requested delete, |
350 | so if your database has a constraint on the relationship, it will |
351 | have deleted/updated the related records or raised an exception |
352 | before DBIx::Class gets to perform the cascaded operation. |
353 | |
354 | =item cascade_update |
355 | |
b7bbc39f |
356 | By default, DBIx::Class cascades updates across C<has_one> and |
5f7ac523 |
357 | C<might_have> relationships. You can disable this behaviour on a |
b7bbc39f |
358 | per-relationship basis by supplying C<< cascade_update => 0 >> in |
359 | the relationship attributes. |
5f7ac523 |
360 | |
9ab122aa |
361 | The C<belongs_to> relationship does not update across relationships |
362 | by default, so if you have a 'proxy' attribute on a belongs_to and want to |
363 | use 'update' on it, you muse set C<< cascade_update => 1 >>. |
364 | |
cee0c9b1 |
365 | This is not a RDMS style cascade update - it purely means that when |
366 | an object has update called on it, all the related objects also |
367 | have update called. It will not change foreign keys automatically - |
368 | you must arrange to do this yourself. |
5f7ac523 |
369 | |
e377d723 |
370 | =item on_delete / on_update |
371 | |
372 | If you are using L<SQL::Translator> to create SQL for you, you can use these |
fd323bf1 |
373 | attributes to explicitly set the desired C<ON DELETE> or C<ON UPDATE> constraint |
374 | type. If not supplied the SQLT parser will attempt to infer the constraint type by |
e377d723 |
375 | interrogating the attributes of the B<opposite> relationship. For any 'multi' |
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376 | relationship with C<< cascade_delete => 1 >>, the corresponding belongs_to |
377 | relationship will be created with an C<ON DELETE CASCADE> constraint. For any |
e377d723 |
378 | relationship bearing C<< cascade_copy => 1 >> the resulting belongs_to constraint |
379 | will be C<ON UPDATE CASCADE>. If you wish to disable this autodetection, and just |
fd323bf1 |
380 | use the RDBMS' default constraint type, pass C<< on_delete => undef >> or |
e377d723 |
381 | C<< on_delete => '' >>, and the same for C<on_update> respectively. |
382 | |
13de943d |
383 | =item is_deferrable |
384 | |
385 | Tells L<SQL::Translator> that the foreign key constraint it creates should be |
386 | deferrable. In other words, the user may request that the constraint be ignored |
387 | until the end of the transaction. Currently, only the PostgreSQL producer |
388 | actually supports this. |
389 | |
2581038c |
390 | =item add_fk_index |
391 | |
392 | Tells L<SQL::Translator> to add an index for this constraint. Can also be |
393 | specified globally in the args to L<DBIx::Class::Schema/deploy> or |
394 | L<DBIx::Class::Schema/create_ddl_dir>. Default is on, set to 0 to disable. |
395 | |
8091aa91 |
396 | =back |
397 | |
87c4e602 |
398 | =head2 register_relationship |
399 | |
27f01d1f |
400 | =over 4 |
401 | |
dad42de6 |
402 | =item Arguments: $rel_name, $rel_info |
27f01d1f |
403 | |
404 | =back |
71e65b39 |
405 | |
30236e47 |
406 | Registers a relationship on the class. This is called internally by |
71f9df37 |
407 | DBIx::Class::ResultSourceProxy to set up Accessors and Proxies. |
71e65b39 |
408 | |
55e2d745 |
409 | =cut |
410 | |
71e65b39 |
411 | sub register_relationship { } |
412 | |
27f01d1f |
413 | =head2 related_resultset |
414 | |
415 | =over 4 |
416 | |
dad42de6 |
417 | =item Arguments: $rel_name |
27f01d1f |
418 | |
dad42de6 |
419 | =item Return Value: L<$related_resultset|DBIx::Class::ResultSet> |
27f01d1f |
420 | |
421 | =back |
30236e47 |
422 | |
27f01d1f |
423 | $rs = $cd->related_resultset('artist'); |
30236e47 |
424 | |
27f01d1f |
425 | Returns a L<DBIx::Class::ResultSet> for the relationship named |
dad42de6 |
426 | $rel_name. |
30236e47 |
427 | |
93711422 |
428 | =head2 $relationship_accessor |
429 | |
430 | =over 4 |
431 | |
dad42de6 |
432 | =item Arguments: none |
93711422 |
433 | |
dad42de6 |
434 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | L<$related_resultset|DBIx::Class::ResultSet> | undef |
93711422 |
435 | |
436 | =back |
437 | |
438 | # These pairs do the same thing |
47d7b769 |
439 | $result = $cd->related_resultset('artist')->single; # has_one relationship |
440 | $result = $cd->artist; |
93711422 |
441 | $rs = $cd->related_resultset('tracks'); # has_many relationship |
442 | $rs = $cd->tracks; |
443 | |
8ed69929 |
444 | This is the recommended way to traverse through relationships, based |
93711422 |
445 | on the L</accessor> name given in the relationship definition. |
446 | |
dad42de6 |
447 | This will return either a L<Result|DBIx::Class::Manual::ResultClass> or a |
93711422 |
448 | L<ResultSet|DBIx::Class::ResultSet>, depending on if the relationship is |
449 | C<single> (returns only one row) or C<multi> (returns many rows). The |
450 | method may also return C<undef> if the relationship doesn't exist for |
451 | this instance (like in the case of C<might_have> relationships). |
452 | |
30236e47 |
453 | =cut |
454 | |
455 | sub related_resultset { |
456 | my $self = shift; |
72c2540d |
457 | |
bc0c9800 |
458 | $self->throw_exception("Can't call *_related as class methods") |
459 | unless ref $self; |
72c2540d |
460 | |
30236e47 |
461 | my $rel = shift; |
d4daee7b |
462 | |
3d0733aa |
463 | return $self->{related_resultsets}{$rel} |
464 | if defined $self->{related_resultsets}{$rel}; |
465 | |
466 | return $self->{related_resultsets}{$rel} = do { |
3b4c4d72 |
467 | |
468 | my $rel_info = $self->relationship_info($rel) |
469 | or $self->throw_exception( "No such relationship '$rel'" ); |
470 | |
30236e47 |
471 | my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {}); |
164efde3 |
472 | $attrs = { %{$rel_info->{attrs} || {}}, %$attrs }; |
30236e47 |
473 | |
bc0c9800 |
474 | $self->throw_exception( "Invalid query: @_" ) |
475 | if (@_ > 1 && (@_ % 2 == 1)); |
30236e47 |
476 | my $query = ((@_ > 1) ? {@_} : shift); |
477 | |
72c2540d |
478 | my $rsrc = $self->result_source; |
d419ded6 |
479 | |
480 | # condition resolution may fail if an incomplete master-object prefetch |
34b6b86f |
481 | # is encountered - that is ok during prefetch construction (not yet in_storage) |
aa56106b |
482 | my ($cond, $is_crosstable) = try { |
72c2540d |
483 | $rsrc->_resolve_condition( $rel_info->{cond}, $rel, $self, $rel ) |
52b420dd |
484 | } |
ed7ab0f4 |
485 | catch { |
f8193780 |
486 | $self->throw_exception ($_) if $self->in_storage; |
487 | $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION; # RV, no return() |
ed7ab0f4 |
488 | }; |
d419ded6 |
489 | |
aa56106b |
490 | # keep in mind that the following if() block is part of a do{} - no return()s!!! |
491 | if ($is_crosstable) { |
492 | $self->throw_exception ( |
e705f529 |
493 | "A cross-table relationship condition returned for statically declared '$rel'" |
494 | ) unless ref $rel_info->{cond} eq 'CODE'; |
aa56106b |
495 | |
496 | # A WHOREIFFIC hack to reinvoke the entire condition resolution |
497 | # with the correct alias. Another way of doing this involves a |
498 | # lot of state passing around, and the @_ positions are already |
499 | # mapped out, making this crap a less icky option. |
500 | # |
501 | # The point of this exercise is to retain the spirit of the original |
502 | # $obj->search_related($rel) where the resulting rset will have the |
503 | # root alias as 'me', instead of $rel (as opposed to invoking |
504 | # $rs->search_related) |
505 | |
72c2540d |
506 | local $rsrc->{_relationships}{me} = $rsrc->{_relationships}{$rel}; # make the fake 'me' rel |
507 | my $obj_table_alias = lc($rsrc->source_name) . '__row'; |
93508f48 |
508 | $obj_table_alias =~ s/\W+/_/g; |
aa56106b |
509 | |
72c2540d |
510 | $rsrc->resultset->search( |
aa56106b |
511 | $self->ident_condition($obj_table_alias), |
512 | { alias => $obj_table_alias }, |
513 | )->search_related('me', $query, $attrs) |
68f3b0dd |
514 | } |
aa56106b |
515 | else { |
516 | # FIXME - this conditional doesn't seem correct - got to figure out |
517 | # at some point what it does. Also the entire UNRESOLVABLE_CONDITION |
518 | # business seems shady - we could simply not query *at all* |
519 | if ($cond eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) { |
72c2540d |
520 | my $reverse = $rsrc->reverse_relationship_info($rel); |
aa56106b |
521 | foreach my $rev_rel (keys %$reverse) { |
522 | if ($reverse->{$rev_rel}{attrs}{accessor} && $reverse->{$rev_rel}{attrs}{accessor} eq 'multi') { |
0a03206a |
523 | weaken($attrs->{related_objects}{$rev_rel}[0] = $self); |
aa56106b |
524 | } else { |
0a03206a |
525 | weaken($attrs->{related_objects}{$rev_rel} = $self); |
aa56106b |
526 | } |
527 | } |
9aae3566 |
528 | } |
aa56106b |
529 | elsif (ref $cond eq 'ARRAY') { |
7689b9e5 |
530 | $cond = [ map { |
531 | if (ref $_ eq 'HASH') { |
532 | my $hash; |
533 | foreach my $key (keys %$_) { |
534 | my $newkey = $key !~ /\./ ? "me.$key" : $key; |
535 | $hash->{$newkey} = $_->{$key}; |
536 | } |
537 | $hash; |
538 | } else { |
539 | $_; |
370f2ba2 |
540 | } |
7689b9e5 |
541 | } @$cond ]; |
aa56106b |
542 | } |
543 | elsif (ref $cond eq 'HASH') { |
544 | foreach my $key (grep { ! /\./ } keys %$cond) { |
7689b9e5 |
545 | $cond->{"me.$key"} = delete $cond->{$key}; |
370f2ba2 |
546 | } |
30236e47 |
547 | } |
a126983e |
548 | |
7689b9e5 |
549 | $query = ($query ? { '-and' => [ $cond, $query ] } : $cond); |
72c2540d |
550 | $rsrc->related_source($rel)->resultset->search( |
aa56106b |
551 | $query, $attrs |
552 | ); |
7689b9e5 |
553 | } |
30236e47 |
554 | }; |
555 | } |
556 | |
8091aa91 |
557 | =head2 search_related |
503536d5 |
558 | |
dad42de6 |
559 | =over 4 |
560 | |
561 | =item Arguments: $rel_name, $cond?, L<\%attrs?|DBIx::Class::ResultSet/ATTRIBUTES> |
562 | |
563 | =item Return Value: L<$resultset|DBIx::Class::ResultSet> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context) |
564 | |
565 | =back |
30236e47 |
566 | |
567 | Run a search on a related resultset. The search will be restricted to the |
dad42de6 |
568 | results represented by the L<DBIx::Class::ResultSet> it was called |
569 | upon. |
570 | |
571 | See L<DBIx::Class::ResultSet/search_related> for more information. |
503536d5 |
572 | |
573 | =cut |
574 | |
55e2d745 |
575 | sub search_related { |
ff7bb7a1 |
576 | return shift->related_resultset(shift)->search(@_); |
b52e9bf8 |
577 | } |
578 | |
5b89a768 |
579 | =head2 search_related_rs |
580 | |
fd323bf1 |
581 | This method works exactly the same as search_related, except that |
48580715 |
582 | it guarantees a resultset, even in list context. |
5b89a768 |
583 | |
584 | =cut |
585 | |
586 | sub search_related_rs { |
587 | return shift->related_resultset(shift)->search_rs(@_); |
588 | } |
589 | |
b52e9bf8 |
590 | =head2 count_related |
591 | |
dad42de6 |
592 | =over 4 |
593 | |
594 | =item Arguments: $rel_name, $cond?, L<\%attrs?|DBIx::Class::ResultSet/ATTRIBUTES> |
595 | |
596 | =item Return Value: $count |
b52e9bf8 |
597 | |
dad42de6 |
598 | =back |
599 | |
600 | Returns the count of all the rows in the related resultset, restricted by the |
601 | current result or where conditions. |
30236e47 |
602 | |
b52e9bf8 |
603 | =cut |
604 | |
605 | sub count_related { |
4b8a53ea |
606 | shift->search_related(@_)->count; |
55e2d745 |
607 | } |
608 | |
30236e47 |
609 | =head2 new_related |
610 | |
dad42de6 |
611 | =over 4 |
612 | |
613 | =item Arguments: $rel_name, \%col_data |
614 | |
615 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
30236e47 |
616 | |
dad42de6 |
617 | =back |
618 | |
619 | Create a new result object of the related foreign class. It will magically set |
620 | any foreign key columns of the new object to the related primary key columns |
621 | of the source object for you. The newly created result will not be saved into |
622 | your storage until you call L<DBIx::Class::Row/insert> on it. |
30236e47 |
623 | |
624 | =cut |
625 | |
626 | sub new_related { |
81e4dc3d |
627 | my ($self, $rel, $values) = @_; |
78b948c3 |
628 | |
629 | # FIXME - this is a bad position for this (also an identical copy in |
630 | # set_from_related), but I have no saner way to hook, and I absolutely |
631 | # want this to throw at least for coderefs, instead of the "insert a NULL |
632 | # when it gets hard" insanity --ribasushi |
633 | # |
634 | # sanity check - currently throw when a complex coderef rel is encountered |
635 | # FIXME - should THROW MOAR! |
636 | |
637 | if (ref $self) { # cdbi calls this as a class method, /me vomits |
638 | |
639 | my $rsrc = $self->result_source; |
3f8affda |
640 | my $rel_info = $rsrc->relationship_info($rel) |
641 | or $self->throw_exception( "No such relationship '$rel'" ); |
f8193780 |
642 | my (undef, $crosstable, $nonequality_foreign_columns) = $rsrc->_resolve_condition ( |
3f8affda |
643 | $rel_info->{cond}, $rel, $self, $rel |
78b948c3 |
644 | ); |
645 | |
646 | $self->throw_exception("Custom relationship '$rel' does not resolve to a join-free condition fragment") |
647 | if $crosstable; |
648 | |
f8193780 |
649 | if ( |
650 | $nonequality_foreign_columns |
651 | and |
652 | my @unspecified_rel_condition_chunks = grep { ! exists $values->{$_} } @$nonequality_foreign_columns |
653 | ) { |
78b948c3 |
654 | $self->throw_exception(sprintf ( |
655 | "Custom relationship '%s' not definitive - returns conditions instead of values for column(s): %s", |
656 | $rel, |
72c2540d |
657 | map { "'$_'" } @unspecified_rel_condition_chunks |
78b948c3 |
658 | )); |
659 | } |
660 | } |
661 | |
81e4dc3d |
662 | return $self->search_related($rel)->new_result($values); |
30236e47 |
663 | } |
664 | |
8091aa91 |
665 | =head2 create_related |
503536d5 |
666 | |
dad42de6 |
667 | =over 4 |
30236e47 |
668 | |
dad42de6 |
669 | =item Arguments: $rel_name, \%col_data |
670 | |
671 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
672 | |
673 | =back |
674 | |
675 | my $result = $obj->create_related($rel_name, \%col_data); |
676 | |
677 | Creates a new result object, similarly to new_related, and also inserts the |
678 | result's data into your storage medium. See the distinction between C<create> |
679 | and C<new> in L<DBIx::Class::ResultSet> for details. |
503536d5 |
680 | |
681 | =cut |
682 | |
55e2d745 |
683 | sub create_related { |
3842b955 |
684 | my $self = shift; |
fea3d045 |
685 | my $rel = shift; |
78b948c3 |
686 | my $obj = $self->new_related($rel, @_)->insert; |
64acc2bc |
687 | delete $self->{related_resultsets}->{$rel}; |
688 | return $obj; |
55e2d745 |
689 | } |
690 | |
8091aa91 |
691 | =head2 find_related |
503536d5 |
692 | |
dad42de6 |
693 | =over 4 |
694 | |
695 | =item Arguments: $rel_name, \%col_data | @pk_values, { key => $unique_constraint, L<%attrs|DBIx::Class::ResultSet/ATTRIBUTES> }? |
696 | |
697 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef |
698 | |
699 | =back |
700 | |
701 | my $result = $obj->find_related($rel_name, \%col_data); |
30236e47 |
702 | |
703 | Attempt to find a related object using its primary key or unique constraints. |
27f01d1f |
704 | See L<DBIx::Class::ResultSet/find> for details. |
503536d5 |
705 | |
706 | =cut |
707 | |
1a14aa3f |
708 | sub find_related { |
4b8a53ea |
709 | #my ($self, $rel, @args) = @_; |
710 | return shift->search_related(shift)->find(@_); |
1a14aa3f |
711 | } |
712 | |
b3e1f1f5 |
713 | =head2 find_or_new_related |
714 | |
dad42de6 |
715 | =over 4 |
b3e1f1f5 |
716 | |
dad42de6 |
717 | =item Arguments: $rel_name, \%col_data, { key => $unique_constraint, L<%attrs|DBIx::Class::ResultSet/ATTRIBUTES> }? |
718 | |
719 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
720 | |
721 | =back |
722 | |
723 | Find a result object of a related class. See L<DBIx::Class::ResultSet/find_or_new> |
724 | for details. |
b3e1f1f5 |
725 | |
726 | =cut |
727 | |
728 | sub find_or_new_related { |
729 | my $self = shift; |
e60dc79f |
730 | my $obj = $self->find_related(@_); |
731 | return defined $obj ? $obj : $self->new_related(@_); |
b3e1f1f5 |
732 | } |
733 | |
8091aa91 |
734 | =head2 find_or_create_related |
503536d5 |
735 | |
dad42de6 |
736 | =over 4 |
737 | |
738 | =item Arguments: $rel_name, \%col_data, { key => $unique_constraint, L<%attrs|DBIx::Class::ResultSet/ATTRIBUTES> }? |
739 | |
740 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
741 | |
742 | =back |
30236e47 |
743 | |
dad42de6 |
744 | Find or create a result object of a related class. See |
b3e1f1f5 |
745 | L<DBIx::Class::ResultSet/find_or_create> for details. |
503536d5 |
746 | |
747 | =cut |
748 | |
55e2d745 |
749 | sub find_or_create_related { |
750 | my $self = shift; |
9c2c91ea |
751 | my $obj = $self->find_related(@_); |
752 | return (defined($obj) ? $obj : $self->create_related(@_)); |
55e2d745 |
753 | } |
754 | |
045120e6 |
755 | =head2 update_or_create_related |
756 | |
dad42de6 |
757 | =over 4 |
758 | |
759 | =item Arguments: $rel_name, \%col_data, { key => $unique_constraint, L<%attrs|DBIx::Class::ResultSet/ATTRIBUTES> }? |
760 | |
761 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
762 | |
763 | =back |
045120e6 |
764 | |
dad42de6 |
765 | Update or create a result object of a related class. See |
f7e1846f |
766 | L<DBIx::Class::ResultSet/update_or_create> for details. |
045120e6 |
767 | |
768 | =cut |
769 | |
770 | sub update_or_create_related { |
4b8a53ea |
771 | #my ($self, $rel, @args) = @_; |
772 | shift->related_resultset(shift)->update_or_create(@_); |
045120e6 |
773 | } |
774 | |
8091aa91 |
775 | =head2 set_from_related |
503536d5 |
776 | |
dad42de6 |
777 | =over 4 |
778 | |
779 | =item Arguments: $rel_name, L<$result|DBIx::Class::Manual::ResultClass> |
780 | |
781 | =item Return Value: not defined |
782 | |
783 | =back |
784 | |
30236e47 |
785 | $book->set_from_related('author', $author_obj); |
ac8e89d7 |
786 | $book->author($author_obj); ## same thing |
30236e47 |
787 | |
788 | Set column values on the current object, using related values from the given |
789 | related object. This is used to associate previously separate objects, for |
790 | example, to set the correct author for a book, find the Author object, then |
791 | call set_from_related on the book. |
792 | |
ac8e89d7 |
793 | This is called internally when you pass existing objects as values to |
48580715 |
794 | L<DBIx::Class::ResultSet/create>, or pass an object to a belongs_to accessor. |
ac8e89d7 |
795 | |
27f01d1f |
796 | The columns are only set in the local copy of the object, call L</update> to |
797 | set them in the storage. |
503536d5 |
798 | |
799 | =cut |
800 | |
55e2d745 |
801 | sub set_from_related { |
802 | my ($self, $rel, $f_obj) = @_; |
aa56106b |
803 | |
78b948c3 |
804 | my $rsrc = $self->result_source; |
805 | my $rel_info = $rsrc->relationship_info($rel) |
e705f529 |
806 | or $self->throw_exception( "No such relationship '$rel'" ); |
aa56106b |
807 | |
2c037e6b |
808 | if (defined $f_obj) { |
164efde3 |
809 | my $f_class = $rel_info->{class}; |
e705f529 |
810 | $self->throw_exception( "Object '$f_obj' isn't a ".$f_class ) |
6298a324 |
811 | unless blessed $f_obj and $f_obj->isa($f_class); |
2c037e6b |
812 | } |
a126983e |
813 | |
a126983e |
814 | |
78b948c3 |
815 | # FIXME - this is a bad position for this (also an identical copy in |
816 | # new_related), but I have no saner way to hook, and I absolutely |
817 | # want this to throw at least for coderefs, instead of the "insert a NULL |
818 | # when it gets hard" insanity --ribasushi |
819 | # |
820 | # sanity check - currently throw when a complex coderef rel is encountered |
821 | # FIXME - should THROW MOAR! |
f8193780 |
822 | my ($cond, $crosstable, $nonequality_foreign_columns) = $rsrc->_resolve_condition ( |
78b948c3 |
823 | $rel_info->{cond}, $f_obj, $rel, $rel |
824 | ); |
825 | $self->throw_exception("Custom relationship '$rel' does not resolve to a join-free condition fragment") |
826 | if $crosstable; |
f8193780 |
827 | |
78b948c3 |
828 | $self->throw_exception(sprintf ( |
829 | "Custom relationship '%s' not definitive - returns conditions instead of values for column(s): %s", |
830 | $rel, |
f8193780 |
831 | map { "'$_'" } @$nonequality_foreign_columns |
832 | )) if $nonequality_foreign_columns; |
aa56106b |
833 | |
834 | $self->set_columns($cond); |
a126983e |
835 | |
55e2d745 |
836 | return 1; |
837 | } |
838 | |
8091aa91 |
839 | =head2 update_from_related |
503536d5 |
840 | |
dad42de6 |
841 | =over 4 |
842 | |
843 | =item Arguments: $rel_name, L<$result|DBIx::Class::Manual::ResultClass> |
844 | |
845 | =item Return Value: not defined |
846 | |
847 | =back |
848 | |
30236e47 |
849 | $book->update_from_related('author', $author_obj); |
850 | |
27f01d1f |
851 | The same as L</"set_from_related">, but the changes are immediately updated |
852 | in storage. |
503536d5 |
853 | |
854 | =cut |
855 | |
55e2d745 |
856 | sub update_from_related { |
857 | my $self = shift; |
858 | $self->set_from_related(@_); |
859 | $self->update; |
860 | } |
861 | |
8091aa91 |
862 | =head2 delete_related |
503536d5 |
863 | |
dad42de6 |
864 | =over 4 |
30236e47 |
865 | |
dad42de6 |
866 | =item Arguments: $rel_name, $cond?, L<\%attrs?|DBIx::Class::ResultSet/ATTRIBUTES> |
867 | |
69bc5f2b |
868 | =item Return Value: $underlying_storage_rv |
dad42de6 |
869 | |
870 | =back |
871 | |
872 | Delete any related row, subject to the given conditions. Internally, this |
873 | calls: |
874 | |
875 | $self->search_related(@_)->delete |
876 | |
877 | And returns the result of that. |
503536d5 |
878 | |
879 | =cut |
880 | |
55e2d745 |
881 | sub delete_related { |
882 | my $self = shift; |
64acc2bc |
883 | my $obj = $self->search_related(@_)->delete; |
884 | delete $self->{related_resultsets}->{$_[0]}; |
885 | return $obj; |
55e2d745 |
886 | } |
887 | |
ec353f53 |
888 | =head2 add_to_$rel |
889 | |
dad42de6 |
890 | B<Currently only available for C<has_many>, C<many_to_many> and 'multi' type |
ec353f53 |
891 | relationships.> |
892 | |
dad42de6 |
893 | =head3 has_many / multi |
894 | |
ec353f53 |
895 | =over 4 |
896 | |
dad42de6 |
897 | =item Arguments: \%col_data |
898 | |
899 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
900 | |
901 | =back |
902 | |
903 | Creates/inserts a new result object. Internally, this calls: |
904 | |
905 | $self->create_related($rel, @_) |
906 | |
907 | And returns the result of that. |
908 | |
909 | =head3 many_to_many |
910 | |
911 | =over 4 |
912 | |
913 | =item Arguments: (\%col_data | L<$result|DBIx::Class::Manual::ResultClass>), \%link_col_data? |
914 | |
915 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
ec353f53 |
916 | |
917 | =back |
918 | |
919 | my $role = $schema->resultset('Role')->find(1); |
920 | $actor->add_to_roles($role); |
dad42de6 |
921 | # creates a My::DBIC::Schema::ActorRoles linking table result object |
ec353f53 |
922 | |
923 | $actor->add_to_roles({ name => 'lead' }, { salary => 15_000_000 }); |
dad42de6 |
924 | # creates a new My::DBIC::Schema::Role result object and the linking table |
ec353f53 |
925 | # object with an extra column in the link |
926 | |
dad42de6 |
927 | Adds a linking table object. If the first argument is a hash reference, the |
928 | related object is created first with the column values in the hash. If an object |
929 | reference is given, just the linking table object is created. In either case, |
930 | any additional column values for the linking table object can be specified in |
931 | C<\%link_col_data>. |
932 | |
933 | See L<DBIx::Class::Relationship/many_to_many> for additional details. |
ec353f53 |
934 | |
935 | =head2 set_$rel |
936 | |
dad42de6 |
937 | B<Currently only available for C<many_to_many> relationships.> |
ec353f53 |
938 | |
939 | =over 4 |
940 | |
dad42de6 |
941 | =item Arguments: (\@hashrefs_of_col_data | L<\@result_objs|DBIx::Class::Manual::ResultClass>), $link_vals? |
942 | |
943 | =item Return Value: not defined |
ec353f53 |
944 | |
945 | =back |
946 | |
947 | my $actor = $schema->resultset('Actor')->find(1); |
fd323bf1 |
948 | my @roles = $schema->resultset('Role')->search({ role => |
debccec3 |
949 | { '-in' => ['Fred', 'Barney'] } } ); |
ec353f53 |
950 | |
4d3a827d |
951 | $actor->set_roles(\@roles); |
952 | # Replaces all of $actor's previous roles with the two named |
ec353f53 |
953 | |
ac36a402 |
954 | $actor->set_roles(\@roles, { salary => 15_000_000 }); |
955 | # Sets a column in the link table for all roles |
956 | |
957 | |
4d3a827d |
958 | Replace all the related objects with the given reference to a list of |
959 | objects. This does a C<delete> B<on the link table resultset> to remove the |
960 | association between the current object and all related objects, then calls |
961 | C<add_to_$rel> repeatedly to link all the new objects. |
bba68c67 |
962 | |
963 | Note that this means that this method will B<not> delete any objects in the |
964 | table on the right side of the relation, merely that it will delete the link |
965 | between them. |
ec353f53 |
966 | |
4d3a827d |
967 | Due to a mistake in the original implementation of this method, it will also |
968 | accept a list of objects or hash references. This is B<deprecated> and will be |
969 | removed in a future version. |
970 | |
ec353f53 |
971 | =head2 remove_from_$rel |
972 | |
dad42de6 |
973 | B<Currently only available for C<many_to_many> relationships.> |
ec353f53 |
974 | |
975 | =over 4 |
976 | |
dad42de6 |
977 | =item Arguments: L<$result|DBIx::Class::Manual::ResultClass> |
978 | |
979 | =item Return Value: not defined |
ec353f53 |
980 | |
981 | =back |
982 | |
983 | my $role = $schema->resultset('Role')->find(1); |
984 | $actor->remove_from_roles($role); |
dad42de6 |
985 | # removes $role's My::DBIC::Schema::ActorRoles linking table result object |
ec353f53 |
986 | |
987 | Removes the link between the current object and the related object. Note that |
988 | the related object itself won't be deleted unless you call ->delete() on |
989 | it. This method just removes the link between the two objects. |
990 | |
0c11ad0e |
991 | =head1 AUTHOR AND CONTRIBUTORS |
55e2d745 |
992 | |
0c11ad0e |
993 | See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class |
55e2d745 |
994 | |
995 | =head1 LICENSE |
996 | |
997 | You may distribute this code under the same terms as Perl itself. |
998 | |
999 | =cut |
1000 | |
4d87db01 |
1001 | 1; |