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89c0a5a2 |
1 | package DBIx::Class::ResultSet; |
2 | |
3 | use strict; |
4 | use warnings; |
5 | use overload |
6 | '0+' => 'count', |
a910dc57 |
7 | 'bool' => sub { 1; }, |
89c0a5a2 |
8 | fallback => 1; |
3c5b25c5 |
9 | use Data::Page; |
ea20d0fd |
10 | use Storable; |
89c0a5a2 |
11 | |
701da8c4 |
12 | use base qw/DBIx::Class/; |
13 | __PACKAGE__->load_components(qw/AccessorGroup/); |
14 | __PACKAGE__->mk_group_accessors('simple' => 'result_source'); |
15 | |
ee38fa40 |
16 | =head1 NAME |
17 | |
bfab575a |
18 | DBIx::Class::ResultSet - Responsible for fetching and creating resultset. |
ee38fa40 |
19 | |
bfab575a |
20 | =head1 SYNOPSIS |
ee38fa40 |
21 | |
a33df5d4 |
22 | my $rs = $schema->resultset('User')->search(registered => 1); |
23 | my @rows = $schema->resultset('Foo')->search(bar => 'baz'); |
ee38fa40 |
24 | |
25 | =head1 DESCRIPTION |
26 | |
bfab575a |
27 | The resultset is also known as an iterator. It is responsible for handling |
a33df5d4 |
28 | queries that may return an arbitrary number of rows, e.g. via L</search> |
bfab575a |
29 | or a C<has_many> relationship. |
ee38fa40 |
30 | |
a33df5d4 |
31 | In the examples below, the following table classes are used: |
32 | |
33 | package MyApp::Schema::Artist; |
34 | use base qw/DBIx::Class/; |
35 | __PACKAGE__->table('artist'); |
36 | __PACKAGE__->add_columns(qw/artistid name/); |
37 | __PACKAGE__->set_primary_key('artistid'); |
38 | __PACKAGE__->has_many(cds => 'MyApp::Schema::CD'); |
39 | 1; |
40 | |
41 | package MyApp::Schema::CD; |
42 | use base qw/DBIx::Class/; |
43 | __PACKAGE__->table('artist'); |
44 | __PACKAGE__->add_columns(qw/cdid artist title year/); |
45 | __PACKAGE__->set_primary_key('cdid'); |
46 | __PACKAGE__->belongs_to(artist => 'MyApp::Schema::Artist'); |
47 | 1; |
48 | |
ee38fa40 |
49 | =head1 METHODS |
50 | |
976f3686 |
51 | =head2 new($source, \%$attrs) |
ee38fa40 |
52 | |
a33df5d4 |
53 | The resultset constructor. Takes a source object (usually a |
80c90f5d |
54 | L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see L</ATRRIBUTES> |
a33df5d4 |
55 | below). Does not perform any queries -- these are executed as needed by the |
56 | other methods. |
57 | |
58 | Generally you won't need to construct a resultset manually. You'll |
59 | automatically get one from e.g. a L</search> called in scalar context: |
60 | |
61 | my $rs = $schema->resultset('CD')->search({ title => '100th Window' }); |
ee38fa40 |
62 | |
63 | =cut |
64 | |
89c0a5a2 |
65 | sub new { |
fea3d045 |
66 | my $class = shift; |
f9db5527 |
67 | return $class->new_result(@_) if ref $class; |
fea3d045 |
68 | my ($source, $attrs) = @_; |
b98e75f6 |
69 | #use Data::Dumper; warn Dumper($attrs); |
ea20d0fd |
70 | $attrs = Storable::dclone($attrs || {}); # { %{ $attrs || {} } }; |
c7ce65e6 |
71 | my %seen; |
6aeb9185 |
72 | my $alias = ($attrs->{alias} ||= 'me'); |
a9433341 |
73 | if ($attrs->{cols} || !$attrs->{select}) { |
74 | delete $attrs->{as} if $attrs->{cols}; |
976f3686 |
75 | my @cols = ($attrs->{cols} |
76 | ? @{delete $attrs->{cols}} |
a9433341 |
77 | : $source->columns); |
6aeb9185 |
78 | $attrs->{select} = [ map { m/\./ ? $_ : "${alias}.$_" } @cols ]; |
976f3686 |
79 | } |
6aeb9185 |
80 | $attrs->{as} ||= [ map { m/^$alias\.(.*)$/ ? $1 : $_ } @{$attrs->{select}} ]; |
976f3686 |
81 | #use Data::Dumper; warn Dumper(@{$attrs}{qw/select as/}); |
fea3d045 |
82 | $attrs->{from} ||= [ { $alias => $source->from } ]; |
b52e9bf8 |
83 | if (my $join = delete $attrs->{join}) { |
84 | foreach my $j (ref $join eq 'ARRAY' |
85 | ? (@{$join}) : ($join)) { |
c7ce65e6 |
86 | if (ref $j eq 'HASH') { |
87 | $seen{$_} = 1 foreach keys %$j; |
88 | } else { |
89 | $seen{$j} = 1; |
90 | } |
91 | } |
8452e496 |
92 | push(@{$attrs->{from}}, $source->resolve_join($join, $attrs->{alias})); |
c7ce65e6 |
93 | } |
54540863 |
94 | $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct}; |
b3e8ac9b |
95 | |
96 | if (my $prefetch = delete $attrs->{prefetch}) { |
97 | foreach my $p (ref $prefetch eq 'ARRAY' |
98 | ? (@{$prefetch}) : ($prefetch)) { |
99 | if( ref $p eq 'HASH' ) { |
100 | foreach my $key (keys %$p) { |
101 | push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias})) |
102 | unless $seen{$key}; |
103 | } |
104 | } |
105 | else { |
106 | push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias})) |
107 | unless $seen{$p}; |
108 | } |
109 | my @cols = (); |
110 | push @cols, $source->resolve_prefetch($p, $attrs->{alias}); |
111 | #die Dumper \@cols; |
112 | push(@{$attrs->{select}}, @cols); |
113 | push(@{$attrs->{as}}, @cols); |
114 | } |
fef5d100 |
115 | } |
b3e8ac9b |
116 | |
6aeb9185 |
117 | if ($attrs->{page}) { |
118 | $attrs->{rows} ||= 10; |
119 | $attrs->{offset} ||= 0; |
120 | $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1)); |
121 | } |
89c0a5a2 |
122 | my $new = { |
701da8c4 |
123 | result_source => $source, |
89c0a5a2 |
124 | cond => $attrs->{where}, |
0a3c5b43 |
125 | from => $attrs->{from}, |
3c5b25c5 |
126 | count => undef, |
93b004d3 |
127 | page => delete $attrs->{page}, |
3c5b25c5 |
128 | pager => undef, |
89c0a5a2 |
129 | attrs => $attrs }; |
2f5911b2 |
130 | bless ($new, $class); |
9229f20a |
131 | return $new; |
89c0a5a2 |
132 | } |
133 | |
bfab575a |
134 | =head2 search |
0a3c5b43 |
135 | |
87f0da6a |
136 | my @obj = $rs->search({ foo => 3 }); # "... WHERE foo = 3" |
137 | my $new_rs = $rs->search({ foo => 3 }); |
138 | |
6009260a |
139 | If you need to pass in additional attributes but no additional condition, |
a33df5d4 |
140 | call it as C<search({}, \%attrs);>. |
87f0da6a |
141 | |
a33df5d4 |
142 | # "SELECT foo, bar FROM $class_table" |
143 | my @all = $class->search({}, { cols => [qw/foo bar/] }); |
0a3c5b43 |
144 | |
145 | =cut |
146 | |
147 | sub search { |
148 | my $self = shift; |
149 | |
6009260a |
150 | #use Data::Dumper;warn Dumper(@_); |
151 | |
0a3c5b43 |
152 | my $attrs = { %{$self->{attrs}} }; |
153 | if (@_ > 1 && ref $_[$#_] eq 'HASH') { |
6aeb9185 |
154 | $attrs = { %$attrs, %{ pop(@_) } }; |
0a3c5b43 |
155 | } |
156 | |
6aeb9185 |
157 | my $where = (@_ ? ((@_ == 1 || ref $_[0] eq "HASH") ? shift : {@_}) : undef()); |
0a3c5b43 |
158 | if (defined $where) { |
159 | $where = (defined $attrs->{where} |
ad3d2d7c |
160 | ? { '-and' => |
161 | [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ } |
162 | $where, $attrs->{where} ] } |
0a3c5b43 |
163 | : $where); |
164 | $attrs->{where} = $where; |
165 | } |
166 | |
701da8c4 |
167 | my $rs = (ref $self)->new($self->result_source, $attrs); |
0a3c5b43 |
168 | |
169 | return (wantarray ? $rs->all : $rs); |
170 | } |
171 | |
87f0da6a |
172 | =head2 search_literal |
173 | |
6009260a |
174 | my @obj = $rs->search_literal($literal_where_cond, @bind); |
175 | my $new_rs = $rs->search_literal($literal_where_cond, @bind); |
176 | |
177 | Pass a literal chunk of SQL to be added to the conditional part of the |
87f0da6a |
178 | resultset. |
6009260a |
179 | |
bfab575a |
180 | =cut |
181 | |
6009260a |
182 | sub search_literal { |
183 | my ($self, $cond, @vals) = @_; |
184 | my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {}); |
185 | $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ]; |
186 | return $self->search(\$cond, $attrs); |
187 | } |
0a3c5b43 |
188 | |
87f0da6a |
189 | =head2 find(@colvalues), find(\%cols, \%attrs?) |
190 | |
191 | Finds a row based on its primary key or unique constraint. For example: |
192 | |
87f0da6a |
193 | my $cd = $schema->resultset('CD')->find(5); |
194 | |
195 | Also takes an optional C<key> attribute, to search by a specific key or unique |
196 | constraint. For example: |
197 | |
198 | my $cd = $schema->resultset('CD')->find_or_create( |
199 | { |
200 | artist => 'Massive Attack', |
201 | title => 'Mezzanine', |
202 | }, |
203 | { key => 'artist_title' } |
204 | ); |
205 | |
a33df5d4 |
206 | See also L</find_or_create> and L</update_or_create>. |
207 | |
87f0da6a |
208 | =cut |
716b3d29 |
209 | |
210 | sub find { |
211 | my ($self, @vals) = @_; |
212 | my $attrs = (@vals > 1 && ref $vals[$#vals] eq 'HASH' ? pop(@vals) : {}); |
87f0da6a |
213 | |
701da8c4 |
214 | my @cols = $self->result_source->primary_columns; |
87f0da6a |
215 | if (exists $attrs->{key}) { |
701da8c4 |
216 | my %uniq = $self->result_source->unique_constraints; |
87f0da6a |
217 | $self->( "Unknown key " . $attrs->{key} . " on " . $self->name ) |
218 | unless exists $uniq{$attrs->{key}}; |
219 | @cols = @{ $uniq{$attrs->{key}} }; |
220 | } |
221 | #use Data::Dumper; warn Dumper($attrs, @vals, @cols); |
701da8c4 |
222 | $self->throw_exception( "Can't find unless a primary key or unique constraint is defined" ) |
87f0da6a |
223 | unless @cols; |
224 | |
716b3d29 |
225 | my $query; |
226 | if (ref $vals[0] eq 'HASH') { |
227 | $query = $vals[0]; |
87f0da6a |
228 | } elsif (@cols == @vals) { |
716b3d29 |
229 | $query = {}; |
87f0da6a |
230 | @{$query}{@cols} = @vals; |
716b3d29 |
231 | } else { |
232 | $query = {@vals}; |
233 | } |
234 | #warn Dumper($query); |
716b3d29 |
235 | return $self->search($query)->next; |
236 | } |
237 | |
b52e9bf8 |
238 | =head2 search_related |
239 | |
240 | $rs->search_related('relname', $cond?, $attrs?); |
241 | |
a33df5d4 |
242 | Search the specified relationship. Optionally specify a condition for matching |
243 | records. |
244 | |
b52e9bf8 |
245 | =cut |
246 | |
6aeb9185 |
247 | sub search_related { |
248 | my ($self, $rel, @rest) = @_; |
701da8c4 |
249 | my $rel_obj = $self->result_source->relationship_info($rel); |
250 | $self->throw_exception( |
6aeb9185 |
251 | "No such relationship ${rel} in search_related") |
252 | unless $rel_obj; |
6aeb9185 |
253 | my $rs = $self->search(undef, { join => $rel }); |
701da8c4 |
254 | return $self->result_source->schema->resultset($rel_obj->{class} |
ea20d0fd |
255 | )->search( undef, |
256 | { %{$rs->{attrs}}, |
257 | alias => $rel, |
258 | select => undef(), |
259 | as => undef() } |
6aeb9185 |
260 | )->search(@rest); |
261 | } |
b52e9bf8 |
262 | |
bfab575a |
263 | =head2 cursor |
ee38fa40 |
264 | |
bfab575a |
265 | Returns a storage-driven cursor to the given resultset. |
ee38fa40 |
266 | |
267 | =cut |
268 | |
73f58123 |
269 | sub cursor { |
270 | my ($self) = @_; |
701da8c4 |
271 | my ($attrs) = $self->{attrs}; |
6aeb9185 |
272 | $attrs = { %$attrs }; |
73f58123 |
273 | return $self->{cursor} |
701da8c4 |
274 | ||= $self->result_source->storage->select($self->{from}, $attrs->{select}, |
73f58123 |
275 | $attrs->{where},$attrs); |
276 | } |
277 | |
87f0da6a |
278 | =head2 search_like |
279 | |
a33df5d4 |
280 | Perform a search, but use C<LIKE> instead of equality as the condition. Note |
281 | that this is simply a convenience method; you most likely want to use |
282 | L</search> with specific operators. |
283 | |
284 | For more information, see L<DBIx::Class::Manual::Cookbook>. |
87f0da6a |
285 | |
286 | =cut |
58a4bd18 |
287 | |
288 | sub search_like { |
289 | my $class = shift; |
290 | my $attrs = { }; |
291 | if (@_ > 1 && ref $_[$#_] eq 'HASH') { |
292 | $attrs = pop(@_); |
293 | } |
294 | my $query = ref $_[0] eq "HASH" ? { %{shift()} }: {@_}; |
295 | $query->{$_} = { 'like' => $query->{$_} } for keys %$query; |
296 | return $class->search($query, { %$attrs }); |
297 | } |
298 | |
bfab575a |
299 | =head2 slice($first, $last) |
ee38fa40 |
300 | |
bfab575a |
301 | Returns a subset of elements from the resultset. |
ee38fa40 |
302 | |
303 | =cut |
304 | |
89c0a5a2 |
305 | sub slice { |
306 | my ($self, $min, $max) = @_; |
307 | my $attrs = { %{ $self->{attrs} || {} } }; |
6aeb9185 |
308 | $attrs->{offset} ||= 0; |
309 | $attrs->{offset} += $min; |
89c0a5a2 |
310 | $attrs->{rows} = ($max ? ($max - $min + 1) : 1); |
701da8c4 |
311 | my $slice = (ref $self)->new($self->result_source, $attrs); |
89c0a5a2 |
312 | return (wantarray ? $slice->all : $slice); |
313 | } |
314 | |
87f0da6a |
315 | =head2 next |
ee38fa40 |
316 | |
a33df5d4 |
317 | Returns the next element in the resultset (C<undef> is there is none). |
318 | |
319 | Can be used to efficiently iterate over records in the resultset: |
320 | |
321 | my $rs = $schema->resultset('CD')->search({}); |
322 | while (my $cd = $rs->next) { |
323 | print $cd->title; |
324 | } |
ee38fa40 |
325 | |
326 | =cut |
327 | |
89c0a5a2 |
328 | sub next { |
329 | my ($self) = @_; |
73f58123 |
330 | my @row = $self->cursor->next; |
a953d8d9 |
331 | # warn Dumper(\@row); use Data::Dumper; |
89c0a5a2 |
332 | return unless (@row); |
c7ce65e6 |
333 | return $self->_construct_object(@row); |
334 | } |
335 | |
336 | sub _construct_object { |
337 | my ($self, @row) = @_; |
b3e8ac9b |
338 | my @as = @{ $self->{attrs}{as} }; |
976f3686 |
339 | #warn "@cols -> @row"; |
b3e8ac9b |
340 | my $info = [ {}, {} ]; |
341 | foreach my $as (@as) { |
342 | my $target = $info; |
343 | my @parts = split(/\./, $as); |
344 | my $col = pop(@parts); |
345 | foreach my $p (@parts) { |
346 | $target = $target->[1]->{$p} ||= []; |
c7ce65e6 |
347 | } |
b3e8ac9b |
348 | $target->[0]->{$col} = shift @row; |
c7ce65e6 |
349 | } |
b3e8ac9b |
350 | #use Data::Dumper; warn Dumper(\@as, $info); |
701da8c4 |
351 | my $new = $self->result_source->result_class->inflate_result( |
352 | $self->result_source, @$info); |
33ce49d6 |
353 | $new = $self->{attrs}{record_filter}->($new) |
354 | if exists $self->{attrs}{record_filter}; |
355 | return $new; |
89c0a5a2 |
356 | } |
357 | |
701da8c4 |
358 | =head2 result_source |
359 | |
360 | Returns a reference to the result source for this recordset. |
361 | |
362 | =cut |
363 | |
364 | |
bfab575a |
365 | =head2 count |
ee38fa40 |
366 | |
bfab575a |
367 | Performs an SQL C<COUNT> with the same query as the resultset was built |
6009260a |
368 | with to find the number of elements. If passed arguments, does a search |
369 | on the resultset and counts the results of that. |
ee38fa40 |
370 | |
371 | =cut |
372 | |
89c0a5a2 |
373 | sub count { |
6009260a |
374 | my $self = shift; |
375 | return $self->search(@_)->count if @_ && defined $_[0]; |
6aeb9185 |
376 | unless (defined $self->{count}) { |
15c382be |
377 | my $group_by; |
378 | my $select = { 'count' => '*' }; |
379 | if( $group_by = delete $self->{attrs}{group_by} ) { |
380 | my @distinct = @$group_by; |
381 | # todo: try CONCAT for multi-column pk |
382 | my @pk = $self->result_source->primary_columns; |
383 | if( scalar(@pk) == 1 ) { |
384 | my $pk = shift(@pk); |
385 | my $alias = $self->{attrs}{alias}; |
386 | my $re = qr/^($alias\.)?$pk$/; |
387 | foreach my $column ( @$group_by ) { |
388 | if( $column =~ $re ) { |
389 | @distinct = ( $column ); |
390 | last; |
391 | } |
392 | } |
393 | } |
394 | |
395 | $select = { count => { 'distinct' => \@distinct } }; |
396 | #use Data::Dumper; die Dumper $select; |
397 | } |
398 | |
976f3686 |
399 | my $attrs = { %{ $self->{attrs} }, |
15c382be |
400 | select => $select, |
54540863 |
401 | as => [ 'count' ] }; |
ea20d0fd |
402 | # offset, order by and page are not needed to count. record_filter is cdbi |
403 | delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/; |
3c5b25c5 |
404 | |
701da8c4 |
405 | ($self->{count}) = (ref $self)->new($self->result_source, $attrs)->cursor->next; |
15c382be |
406 | $self->{attrs}{group_by} = $group_by; |
3c5b25c5 |
407 | } |
408 | return 0 unless $self->{count}; |
6aeb9185 |
409 | my $count = $self->{count}; |
410 | $count -= $self->{attrs}{offset} if $self->{attrs}{offset}; |
411 | $count = $self->{attrs}{rows} if |
412 | ($self->{attrs}{rows} && $self->{attrs}{rows} < $count); |
413 | return $count; |
89c0a5a2 |
414 | } |
415 | |
bfab575a |
416 | =head2 count_literal |
6009260a |
417 | |
a33df5d4 |
418 | Calls L</search_literal> with the passed arguments, then L</count>. |
6009260a |
419 | |
420 | =cut |
421 | |
422 | sub count_literal { shift->search_literal(@_)->count; } |
423 | |
bfab575a |
424 | =head2 all |
ee38fa40 |
425 | |
bfab575a |
426 | Returns all elements in the resultset. Called implictly if the resultset |
427 | is returned in list context. |
ee38fa40 |
428 | |
429 | =cut |
430 | |
89c0a5a2 |
431 | sub all { |
432 | my ($self) = @_; |
c7ce65e6 |
433 | return map { $self->_construct_object(@$_); } |
73f58123 |
434 | $self->cursor->all; |
89c0a5a2 |
435 | } |
436 | |
bfab575a |
437 | =head2 reset |
ee38fa40 |
438 | |
bfab575a |
439 | Resets the resultset's cursor, so you can iterate through the elements again. |
ee38fa40 |
440 | |
441 | =cut |
442 | |
89c0a5a2 |
443 | sub reset { |
444 | my ($self) = @_; |
73f58123 |
445 | $self->cursor->reset; |
89c0a5a2 |
446 | return $self; |
447 | } |
448 | |
bfab575a |
449 | =head2 first |
ee38fa40 |
450 | |
bfab575a |
451 | Resets the resultset and returns the first element. |
ee38fa40 |
452 | |
453 | =cut |
454 | |
89c0a5a2 |
455 | sub first { |
456 | return $_[0]->reset->next; |
457 | } |
458 | |
c01ab172 |
459 | =head2 update(\%values) |
460 | |
a33df5d4 |
461 | Sets the specified columns in the resultset to the supplied values. |
c01ab172 |
462 | |
463 | =cut |
464 | |
465 | sub update { |
466 | my ($self, $values) = @_; |
701da8c4 |
467 | $self->throw_exception("Values for update must be a hash") unless ref $values eq 'HASH'; |
468 | return $self->result_source->storage->update( |
469 | $self->result_source->from, $values, $self->{cond}); |
c01ab172 |
470 | } |
471 | |
472 | =head2 update_all(\%values) |
473 | |
a33df5d4 |
474 | Fetches all objects and updates them one at a time. Note that C<update_all> |
475 | will run cascade triggers while L</update> will not. |
c01ab172 |
476 | |
477 | =cut |
478 | |
479 | sub update_all { |
480 | my ($self, $values) = @_; |
701da8c4 |
481 | $self->throw_exception("Values for update must be a hash") unless ref $values eq 'HASH'; |
c01ab172 |
482 | foreach my $obj ($self->all) { |
483 | $obj->set_columns($values)->update; |
484 | } |
485 | return 1; |
486 | } |
487 | |
bfab575a |
488 | =head2 delete |
ee38fa40 |
489 | |
c01ab172 |
490 | Deletes the contents of the resultset from its result source. |
ee38fa40 |
491 | |
492 | =cut |
493 | |
28927b50 |
494 | sub delete { |
89c0a5a2 |
495 | my ($self) = @_; |
701da8c4 |
496 | $self->result_source->storage->delete($self->result_source->from, $self->{cond}); |
89c0a5a2 |
497 | return 1; |
498 | } |
499 | |
c01ab172 |
500 | =head2 delete_all |
501 | |
a33df5d4 |
502 | Fetches all objects and deletes them one at a time. Note that C<delete_all> |
503 | will run cascade triggers while L</delete> will not. |
c01ab172 |
504 | |
505 | =cut |
506 | |
507 | sub delete_all { |
508 | my ($self) = @_; |
509 | $_->delete for $self->all; |
510 | return 1; |
511 | } |
28927b50 |
512 | |
bfab575a |
513 | =head2 pager |
ee38fa40 |
514 | |
515 | Returns a L<Data::Page> object for the current resultset. Only makes |
a33df5d4 |
516 | sense for queries with a C<page> attribute. |
ee38fa40 |
517 | |
518 | =cut |
519 | |
3c5b25c5 |
520 | sub pager { |
521 | my ($self) = @_; |
522 | my $attrs = $self->{attrs}; |
701da8c4 |
523 | $self->throw_exception("Can't create pager for non-paged rs") unless $self->{page}; |
6aeb9185 |
524 | $attrs->{rows} ||= 10; |
525 | $self->count; |
526 | return $self->{pager} ||= Data::Page->new( |
93b004d3 |
527 | $self->{count}, $attrs->{rows}, $self->{page}); |
3c5b25c5 |
528 | } |
529 | |
bfab575a |
530 | =head2 page($page_num) |
ee38fa40 |
531 | |
bfab575a |
532 | Returns a new resultset for the specified page. |
ee38fa40 |
533 | |
534 | =cut |
535 | |
3c5b25c5 |
536 | sub page { |
537 | my ($self, $page) = @_; |
6aeb9185 |
538 | my $attrs = { %{$self->{attrs}} }; |
3c5b25c5 |
539 | $attrs->{page} = $page; |
701da8c4 |
540 | return (ref $self)->new($self->result_source, $attrs); |
fea3d045 |
541 | } |
542 | |
543 | =head2 new_result(\%vals) |
544 | |
87f0da6a |
545 | Creates a result in the resultset's result class. |
fea3d045 |
546 | |
547 | =cut |
548 | |
549 | sub new_result { |
550 | my ($self, $values) = @_; |
701da8c4 |
551 | $self->throw_exception( "new_result needs a hash" ) |
fea3d045 |
552 | unless (ref $values eq 'HASH'); |
701da8c4 |
553 | $self->throw_exception( "Can't abstract implicit construct, condition not a hash" ) |
fea3d045 |
554 | if ($self->{cond} && !(ref $self->{cond} eq 'HASH')); |
555 | my %new = %$values; |
556 | my $alias = $self->{attrs}{alias}; |
557 | foreach my $key (keys %{$self->{cond}||{}}) { |
558 | $new{$1} = $self->{cond}{$key} if ($key =~ m/^(?:$alias\.)?([^\.]+)$/); |
559 | } |
701da8c4 |
560 | my $obj = $self->result_source->result_class->new(\%new); |
561 | $obj->result_source($self->result_source) if $obj->can('result_source'); |
097d3227 |
562 | $obj; |
fea3d045 |
563 | } |
564 | |
565 | =head2 create(\%vals) |
566 | |
87f0da6a |
567 | Inserts a record into the resultset and returns the object. |
fea3d045 |
568 | |
a33df5d4 |
569 | Effectively a shortcut for C<< ->new_result(\%vals)->insert >>. |
fea3d045 |
570 | |
571 | =cut |
572 | |
573 | sub create { |
574 | my ($self, $attrs) = @_; |
701da8c4 |
575 | $self->throw_exception( "create needs a hashref" ) unless ref $attrs eq 'HASH'; |
fea3d045 |
576 | return $self->new_result($attrs)->insert; |
3c5b25c5 |
577 | } |
578 | |
87f0da6a |
579 | =head2 find_or_create(\%vals, \%attrs?) |
580 | |
581 | $class->find_or_create({ key => $val, ... }); |
c2b15ecc |
582 | |
c2b15ecc |
583 | Searches for a record matching the search condition; if it doesn't find one, |
cf7b40ed |
584 | creates one and returns that instead. |
87f0da6a |
585 | |
87f0da6a |
586 | my $cd = $schema->resultset('CD')->find_or_create({ |
587 | cdid => 5, |
588 | artist => 'Massive Attack', |
589 | title => 'Mezzanine', |
590 | year => 2005, |
591 | }); |
592 | |
593 | Also takes an optional C<key> attribute, to search by a specific key or unique |
594 | constraint. For example: |
595 | |
596 | my $cd = $schema->resultset('CD')->find_or_create( |
597 | { |
598 | artist => 'Massive Attack', |
599 | title => 'Mezzanine', |
600 | }, |
601 | { key => 'artist_title' } |
602 | ); |
603 | |
604 | See also L</find> and L</update_or_create>. |
605 | |
c2b15ecc |
606 | =cut |
607 | |
608 | sub find_or_create { |
609 | my $self = shift; |
87f0da6a |
610 | my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {}); |
611 | my $hash = ref $_[0] eq "HASH" ? shift : {@_}; |
612 | my $exists = $self->find($hash, $attrs); |
c2b15ecc |
613 | return defined($exists) ? $exists : $self->create($hash); |
614 | } |
615 | |
87f0da6a |
616 | =head2 update_or_create |
617 | |
618 | $class->update_or_create({ key => $val, ... }); |
619 | |
620 | First, search for an existing row matching one of the unique constraints |
621 | (including the primary key) on the source of this resultset. If a row is |
622 | found, update it with the other given column values. Otherwise, create a new |
623 | row. |
624 | |
625 | Takes an optional C<key> attribute to search on a specific unique constraint. |
626 | For example: |
627 | |
628 | # In your application |
629 | my $cd = $schema->resultset('CD')->update_or_create( |
630 | { |
631 | artist => 'Massive Attack', |
632 | title => 'Mezzanine', |
633 | year => 1998, |
634 | }, |
635 | { key => 'artist_title' } |
636 | ); |
637 | |
638 | If no C<key> is specified, it searches on all unique constraints defined on the |
639 | source, including the primary key. |
640 | |
641 | If the C<key> is specified as C<primary>, search only on the primary key. |
642 | |
a33df5d4 |
643 | See also L</find> and L</find_or_create>. |
644 | |
87f0da6a |
645 | =cut |
646 | |
647 | sub update_or_create { |
648 | my $self = shift; |
649 | |
650 | my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {}); |
651 | my $hash = ref $_[0] eq "HASH" ? shift : {@_}; |
652 | |
701da8c4 |
653 | my %unique_constraints = $self->result_source->unique_constraints; |
87f0da6a |
654 | my @constraint_names = (exists $attrs->{key} |
655 | ? ($attrs->{key}) |
656 | : keys %unique_constraints); |
657 | |
658 | my @unique_hashes; |
659 | foreach my $name (@constraint_names) { |
660 | my @unique_cols = @{ $unique_constraints{$name} }; |
661 | my %unique_hash = |
662 | map { $_ => $hash->{$_} } |
663 | grep { exists $hash->{$_} } |
664 | @unique_cols; |
665 | |
666 | push @unique_hashes, \%unique_hash |
667 | if (scalar keys %unique_hash == scalar @unique_cols); |
668 | } |
669 | |
670 | my $row; |
671 | if (@unique_hashes) { |
672 | $row = $self->search(\@unique_hashes, { rows => 1 })->first; |
673 | if ($row) { |
674 | $row->set_columns($hash); |
675 | $row->update; |
676 | } |
677 | } |
678 | |
679 | unless ($row) { |
680 | $row = $self->create($hash); |
681 | } |
682 | |
683 | return $row; |
684 | } |
685 | |
701da8c4 |
686 | =head2 throw_exception |
687 | |
688 | See Schema's throw_exception |
689 | |
690 | =cut |
691 | |
692 | sub throw_exception { |
693 | my $self=shift; |
694 | $self->result_source->schema->throw_exception(@_); |
695 | } |
696 | |
40dbc108 |
697 | =head1 ATTRIBUTES |
076652e8 |
698 | |
a33df5d4 |
699 | The resultset takes various attributes that modify its behavior. Here's an |
700 | overview of them: |
bfab575a |
701 | |
702 | =head2 order_by |
076652e8 |
703 | |
a33df5d4 |
704 | Which column(s) to order the results by. This is currently passed through |
705 | directly to SQL, so you can give e.g. C<foo DESC> for a descending order. |
076652e8 |
706 | |
976f3686 |
707 | =head2 cols (arrayref) |
708 | |
a33df5d4 |
709 | Shortcut to request a particular set of columns to be retrieved. Adds |
710 | C<me.> onto the start of any column without a C<.> in it and sets C<select> |
711 | from that, then auto-populates C<as> from C<select> as normal. |
976f3686 |
712 | |
713 | =head2 select (arrayref) |
714 | |
4a28c340 |
715 | Indicates which columns should be selected from the storage. You can use |
716 | column names, or in the case of RDBMS back ends, function or stored procedure |
717 | names: |
718 | |
719 | $rs = $schema->resultset('Foo')->search( |
720 | {}, |
721 | { |
cf7b40ed |
722 | select => [ |
4a28c340 |
723 | 'column_name', |
724 | { count => 'column_to_count' }, |
725 | { sum => 'column_to_sum' } |
cf7b40ed |
726 | ] |
4a28c340 |
727 | } |
728 | ); |
729 | |
730 | When you use function/stored procedure names and do not supply an C<as> |
731 | attribute, the column names returned are storage-dependent. E.g. MySQL would |
732 | return a column named C<count(column_to_count)> in the above example. |
976f3686 |
733 | |
734 | =head2 as (arrayref) |
076652e8 |
735 | |
4a28c340 |
736 | Indicates column names for object inflation. This is used in conjunction with |
737 | C<select>, usually when C<select> contains one or more function or stored |
738 | procedure names: |
739 | |
740 | $rs = $schema->resultset('Foo')->search( |
741 | {}, |
742 | { |
cf7b40ed |
743 | select => [ |
4a28c340 |
744 | 'column1', |
745 | { count => 'column2' } |
cf7b40ed |
746 | ], |
4a28c340 |
747 | as => [qw/ column1 column2_count /] |
748 | } |
749 | ); |
750 | |
751 | my $foo = $rs->first(); # get the first Foo |
752 | |
753 | If the object against which the search is performed already has an accessor |
754 | matching a column name specified in C<as>, the value can be retrieved using |
755 | the accessor as normal: |
756 | |
757 | my $column1 = $foo->column1(); |
758 | |
759 | If on the other hand an accessor does not exist in the object, you need to |
760 | use C<get_column> instead: |
761 | |
762 | my $column2_count = $foo->get_column('column2_count'); |
763 | |
764 | You can create your own accessors if required - see |
765 | L<DBIx::Class::Manual::Cookbook> for details. |
ee38fa40 |
766 | |
bfab575a |
767 | =head2 join |
ee38fa40 |
768 | |
a33df5d4 |
769 | Contains a list of relationships that should be joined for this query. For |
770 | example: |
771 | |
772 | # Get CDs by Nine Inch Nails |
773 | my $rs = $schema->resultset('CD')->search( |
774 | { 'artist.name' => 'Nine Inch Nails' }, |
775 | { join => 'artist' } |
776 | ); |
777 | |
778 | Can also contain a hash reference to refer to the other relation's relations. |
779 | For example: |
780 | |
781 | package MyApp::Schema::Track; |
782 | use base qw/DBIx::Class/; |
783 | __PACKAGE__->table('track'); |
784 | __PACKAGE__->add_columns(qw/trackid cd position title/); |
785 | __PACKAGE__->set_primary_key('trackid'); |
786 | __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD'); |
787 | 1; |
788 | |
789 | # In your application |
790 | my $rs = $schema->resultset('Artist')->search( |
791 | { 'track.title' => 'Teardrop' }, |
792 | { |
793 | join => { cd => 'track' }, |
794 | order_by => 'artist.name', |
795 | } |
796 | ); |
797 | |
ae1c90a1 |
798 | If you want to fetch columns from related tables as well, see C<prefetch> |
799 | below. |
ee38fa40 |
800 | |
ae1c90a1 |
801 | =head2 prefetch arrayref/hashref |
ee38fa40 |
802 | |
ae1c90a1 |
803 | Contains one or more relationships that should be fetched along with the main |
bfab575a |
804 | query (when they are accessed afterwards they will have already been |
a33df5d4 |
805 | "prefetched"). This is useful for when you know you will need the related |
ae1c90a1 |
806 | objects, because it saves at least one query: |
807 | |
808 | my $rs = $schema->resultset('Tag')->search( |
809 | {}, |
810 | { |
811 | prefetch => { |
812 | cd => 'artist' |
813 | } |
814 | } |
815 | ); |
816 | |
817 | The initial search results in SQL like the following: |
818 | |
819 | SELECT tag.*, cd.*, artist.* FROM tag |
820 | JOIN cd ON tag.cd = cd.cdid |
821 | JOIN artist ON cd.artist = artist.artistid |
822 | |
823 | L<DBIx::Class> has no need to go back to the database when we access the |
824 | C<cd> or C<artist> relationships, which saves us two SQL statements in this |
825 | case. |
826 | |
827 | Any prefetched relationship will be joined automatically, so there is no need |
828 | for a C<join> attribute in the above search. |
829 | |
830 | C<prefetch> can be used with the following relationship types: C<belongs_to>, |
831 | C<has_one>. |
ee38fa40 |
832 | |
4a28c340 |
833 | =head2 from (arrayref) |
ee38fa40 |
834 | |
4a28c340 |
835 | The C<from> attribute gives you manual control over the C<FROM> clause of SQL |
836 | statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN> |
837 | clauses. |
ee38fa40 |
838 | |
a33df5d4 |
839 | NOTE: Use this on your own risk. This allows you to shoot off your foot! |
4a28c340 |
840 | C<join> will usually do what you need and it is strongly recommended that you |
841 | avoid using C<from> unless you cannot achieve the desired result using C<join>. |
842 | |
843 | In simple terms, C<from> works as follows: |
844 | |
845 | [ |
846 | { <alias> => <table>, -join-type => 'inner|left|right' } |
847 | [] # nested JOIN (optional) |
848 | { <table.column> = <foreign_table.foreign_key> } |
849 | ] |
850 | |
851 | JOIN |
852 | <alias> <table> |
853 | [JOIN ...] |
854 | ON <table.column> = <foreign_table.foreign_key> |
855 | |
856 | An easy way to follow the examples below is to remember the following: |
857 | |
858 | Anything inside "[]" is a JOIN |
859 | Anything inside "{}" is a condition for the enclosing JOIN |
860 | |
861 | The following examples utilize a "person" table in a family tree application. |
862 | In order to express parent->child relationships, this table is self-joined: |
863 | |
864 | # Person->belongs_to('father' => 'Person'); |
865 | # Person->belongs_to('mother' => 'Person'); |
866 | |
867 | C<from> can be used to nest joins. Here we return all children with a father, |
868 | then search against all mothers of those children: |
869 | |
870 | $rs = $schema->resultset('Person')->search( |
871 | {}, |
872 | { |
873 | alias => 'mother', # alias columns in accordance with "from" |
874 | from => [ |
875 | { mother => 'person' }, |
876 | [ |
877 | [ |
878 | { child => 'person' }, |
879 | [ |
880 | { father => 'person' }, |
881 | { 'father.person_id' => 'child.father_id' } |
882 | ] |
883 | ], |
884 | { 'mother.person_id' => 'child.mother_id' } |
885 | ], |
886 | ] |
887 | }, |
888 | ); |
889 | |
890 | # Equivalent SQL: |
891 | # SELECT mother.* FROM person mother |
892 | # JOIN ( |
893 | # person child |
894 | # JOIN person father |
895 | # ON ( father.person_id = child.father_id ) |
896 | # ) |
897 | # ON ( mother.person_id = child.mother_id ) |
898 | |
899 | The type of any join can be controlled manually. To search against only people |
900 | with a father in the person table, we could explicitly use C<INNER JOIN>: |
901 | |
902 | $rs = $schema->resultset('Person')->search( |
903 | {}, |
904 | { |
905 | alias => 'child', # alias columns in accordance with "from" |
906 | from => [ |
907 | { child => 'person' }, |
908 | [ |
909 | { father => 'person', -join-type => 'inner' }, |
910 | { 'father.id' => 'child.father_id' } |
911 | ], |
912 | ] |
913 | }, |
914 | ); |
915 | |
916 | # Equivalent SQL: |
917 | # SELECT child.* FROM person child |
918 | # INNER JOIN person father ON child.father_id = father.id |
ee38fa40 |
919 | |
bfab575a |
920 | =head2 page |
076652e8 |
921 | |
a33df5d4 |
922 | For a paged resultset, specifies which page to retrieve. Leave unset |
bfab575a |
923 | for an unpaged resultset. |
076652e8 |
924 | |
bfab575a |
925 | =head2 rows |
076652e8 |
926 | |
4a28c340 |
927 | For a paged resultset, how many rows per page: |
928 | |
929 | rows => 10 |
930 | |
931 | Can also be used to simulate an SQL C<LIMIT>. |
076652e8 |
932 | |
a33df5d4 |
933 | =head2 group_by (arrayref) |
54540863 |
934 | |
4a28c340 |
935 | A arrayref of columns to group by. Can include columns of joined tables. Note |
936 | note that L</count> doesn't work on grouped resultsets. |
54540863 |
937 | |
675ce4a6 |
938 | group_by => [qw/ column1 column2 ... /] |
939 | |
54540863 |
940 | =head2 distinct |
941 | |
a33df5d4 |
942 | Set to 1 to group by all columns. |
943 | |
944 | For more examples of using these attributes, see |
945 | L<DBIx::Class::Manual::Cookbook>. |
54540863 |
946 | |
bfab575a |
947 | =cut |
076652e8 |
948 | |
89c0a5a2 |
949 | 1; |