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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 | |
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53 | The resultset constructor. Takes a source object (usually a |
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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}} ]; |
5ac6a044 |
81 | if (my $include = delete $attrs->{include_columns}) { |
82 | push(@{$attrs->{select}}, @$include); |
83 | push(@{$attrs->{as}}, map { m/([^\.]+)$/; $1; } @$include); |
84 | } |
976f3686 |
85 | #use Data::Dumper; warn Dumper(@{$attrs}{qw/select as/}); |
fea3d045 |
86 | $attrs->{from} ||= [ { $alias => $source->from } ]; |
b52e9bf8 |
87 | if (my $join = delete $attrs->{join}) { |
88 | foreach my $j (ref $join eq 'ARRAY' |
89 | ? (@{$join}) : ($join)) { |
c7ce65e6 |
90 | if (ref $j eq 'HASH') { |
91 | $seen{$_} = 1 foreach keys %$j; |
92 | } else { |
93 | $seen{$j} = 1; |
94 | } |
95 | } |
8452e496 |
96 | push(@{$attrs->{from}}, $source->resolve_join($join, $attrs->{alias})); |
c7ce65e6 |
97 | } |
54540863 |
98 | $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct}; |
b3e8ac9b |
99 | |
100 | if (my $prefetch = delete $attrs->{prefetch}) { |
101 | foreach my $p (ref $prefetch eq 'ARRAY' |
102 | ? (@{$prefetch}) : ($prefetch)) { |
103 | if( ref $p eq 'HASH' ) { |
104 | foreach my $key (keys %$p) { |
105 | push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias})) |
106 | unless $seen{$key}; |
107 | } |
108 | } |
109 | else { |
110 | push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias})) |
111 | unless $seen{$p}; |
112 | } |
113 | my @cols = (); |
114 | push @cols, $source->resolve_prefetch($p, $attrs->{alias}); |
115 | #die Dumper \@cols; |
116 | push(@{$attrs->{select}}, @cols); |
117 | push(@{$attrs->{as}}, @cols); |
118 | } |
fef5d100 |
119 | } |
b3e8ac9b |
120 | |
6aeb9185 |
121 | if ($attrs->{page}) { |
122 | $attrs->{rows} ||= 10; |
123 | $attrs->{offset} ||= 0; |
124 | $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1)); |
125 | } |
89c0a5a2 |
126 | my $new = { |
701da8c4 |
127 | result_source => $source, |
89c0a5a2 |
128 | cond => $attrs->{where}, |
0a3c5b43 |
129 | from => $attrs->{from}, |
3c5b25c5 |
130 | count => undef, |
93b004d3 |
131 | page => delete $attrs->{page}, |
3c5b25c5 |
132 | pager => undef, |
89c0a5a2 |
133 | attrs => $attrs }; |
2f5911b2 |
134 | bless ($new, $class); |
9229f20a |
135 | return $new; |
89c0a5a2 |
136 | } |
137 | |
bfab575a |
138 | =head2 search |
0a3c5b43 |
139 | |
87f0da6a |
140 | my @obj = $rs->search({ foo => 3 }); # "... WHERE foo = 3" |
141 | my $new_rs = $rs->search({ foo => 3 }); |
142 | |
6009260a |
143 | If you need to pass in additional attributes but no additional condition, |
a33df5d4 |
144 | call it as C<search({}, \%attrs);>. |
87f0da6a |
145 | |
a33df5d4 |
146 | # "SELECT foo, bar FROM $class_table" |
147 | my @all = $class->search({}, { cols => [qw/foo bar/] }); |
0a3c5b43 |
148 | |
149 | =cut |
150 | |
151 | sub search { |
152 | my $self = shift; |
153 | |
6009260a |
154 | #use Data::Dumper;warn Dumper(@_); |
155 | |
0a3c5b43 |
156 | my $attrs = { %{$self->{attrs}} }; |
157 | if (@_ > 1 && ref $_[$#_] eq 'HASH') { |
6aeb9185 |
158 | $attrs = { %$attrs, %{ pop(@_) } }; |
0a3c5b43 |
159 | } |
160 | |
6aeb9185 |
161 | my $where = (@_ ? ((@_ == 1 || ref $_[0] eq "HASH") ? shift : {@_}) : undef()); |
0a3c5b43 |
162 | if (defined $where) { |
163 | $where = (defined $attrs->{where} |
ad3d2d7c |
164 | ? { '-and' => |
165 | [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ } |
166 | $where, $attrs->{where} ] } |
0a3c5b43 |
167 | : $where); |
168 | $attrs->{where} = $where; |
169 | } |
170 | |
701da8c4 |
171 | my $rs = (ref $self)->new($self->result_source, $attrs); |
0a3c5b43 |
172 | |
173 | return (wantarray ? $rs->all : $rs); |
174 | } |
175 | |
87f0da6a |
176 | =head2 search_literal |
177 | |
6009260a |
178 | my @obj = $rs->search_literal($literal_where_cond, @bind); |
179 | my $new_rs = $rs->search_literal($literal_where_cond, @bind); |
180 | |
181 | Pass a literal chunk of SQL to be added to the conditional part of the |
87f0da6a |
182 | resultset. |
6009260a |
183 | |
bfab575a |
184 | =cut |
185 | |
6009260a |
186 | sub search_literal { |
187 | my ($self, $cond, @vals) = @_; |
188 | my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {}); |
189 | $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ]; |
190 | return $self->search(\$cond, $attrs); |
191 | } |
0a3c5b43 |
192 | |
87f0da6a |
193 | =head2 find(@colvalues), find(\%cols, \%attrs?) |
194 | |
195 | Finds a row based on its primary key or unique constraint. For example: |
196 | |
87f0da6a |
197 | my $cd = $schema->resultset('CD')->find(5); |
198 | |
199 | Also takes an optional C<key> attribute, to search by a specific key or unique |
200 | constraint. For example: |
201 | |
202 | my $cd = $schema->resultset('CD')->find_or_create( |
203 | { |
204 | artist => 'Massive Attack', |
205 | title => 'Mezzanine', |
206 | }, |
207 | { key => 'artist_title' } |
208 | ); |
209 | |
a33df5d4 |
210 | See also L</find_or_create> and L</update_or_create>. |
211 | |
87f0da6a |
212 | =cut |
716b3d29 |
213 | |
214 | sub find { |
215 | my ($self, @vals) = @_; |
216 | my $attrs = (@vals > 1 && ref $vals[$#vals] eq 'HASH' ? pop(@vals) : {}); |
87f0da6a |
217 | |
701da8c4 |
218 | my @cols = $self->result_source->primary_columns; |
87f0da6a |
219 | if (exists $attrs->{key}) { |
701da8c4 |
220 | my %uniq = $self->result_source->unique_constraints; |
87f0da6a |
221 | $self->( "Unknown key " . $attrs->{key} . " on " . $self->name ) |
222 | unless exists $uniq{$attrs->{key}}; |
223 | @cols = @{ $uniq{$attrs->{key}} }; |
224 | } |
225 | #use Data::Dumper; warn Dumper($attrs, @vals, @cols); |
701da8c4 |
226 | $self->throw_exception( "Can't find unless a primary key or unique constraint is defined" ) |
87f0da6a |
227 | unless @cols; |
228 | |
716b3d29 |
229 | my $query; |
230 | if (ref $vals[0] eq 'HASH') { |
01bc091e |
231 | $query = { %{$vals[0]} }; |
87f0da6a |
232 | } elsif (@cols == @vals) { |
716b3d29 |
233 | $query = {}; |
87f0da6a |
234 | @{$query}{@cols} = @vals; |
716b3d29 |
235 | } else { |
236 | $query = {@vals}; |
237 | } |
01bc091e |
238 | foreach (keys %$query) { |
239 | next if m/\./; |
240 | $query->{$self->{attrs}{alias}.'.'.$_} = delete $query->{$_}; |
241 | } |
716b3d29 |
242 | #warn Dumper($query); |
716b3d29 |
243 | return $self->search($query)->next; |
244 | } |
245 | |
b52e9bf8 |
246 | =head2 search_related |
247 | |
248 | $rs->search_related('relname', $cond?, $attrs?); |
249 | |
a33df5d4 |
250 | Search the specified relationship. Optionally specify a condition for matching |
251 | records. |
252 | |
b52e9bf8 |
253 | =cut |
254 | |
6aeb9185 |
255 | sub search_related { |
256 | my ($self, $rel, @rest) = @_; |
701da8c4 |
257 | my $rel_obj = $self->result_source->relationship_info($rel); |
258 | $self->throw_exception( |
6aeb9185 |
259 | "No such relationship ${rel} in search_related") |
260 | unless $rel_obj; |
6aeb9185 |
261 | my $rs = $self->search(undef, { join => $rel }); |
701da8c4 |
262 | return $self->result_source->schema->resultset($rel_obj->{class} |
ea20d0fd |
263 | )->search( undef, |
264 | { %{$rs->{attrs}}, |
265 | alias => $rel, |
266 | select => undef(), |
267 | as => undef() } |
6aeb9185 |
268 | )->search(@rest); |
269 | } |
b52e9bf8 |
270 | |
bfab575a |
271 | =head2 cursor |
ee38fa40 |
272 | |
bfab575a |
273 | Returns a storage-driven cursor to the given resultset. |
ee38fa40 |
274 | |
275 | =cut |
276 | |
73f58123 |
277 | sub cursor { |
278 | my ($self) = @_; |
701da8c4 |
279 | my ($attrs) = $self->{attrs}; |
6aeb9185 |
280 | $attrs = { %$attrs }; |
73f58123 |
281 | return $self->{cursor} |
701da8c4 |
282 | ||= $self->result_source->storage->select($self->{from}, $attrs->{select}, |
73f58123 |
283 | $attrs->{where},$attrs); |
284 | } |
285 | |
87f0da6a |
286 | =head2 search_like |
287 | |
a33df5d4 |
288 | Perform a search, but use C<LIKE> instead of equality as the condition. Note |
289 | that this is simply a convenience method; you most likely want to use |
290 | L</search> with specific operators. |
291 | |
292 | For more information, see L<DBIx::Class::Manual::Cookbook>. |
87f0da6a |
293 | |
294 | =cut |
58a4bd18 |
295 | |
296 | sub search_like { |
297 | my $class = shift; |
298 | my $attrs = { }; |
299 | if (@_ > 1 && ref $_[$#_] eq 'HASH') { |
300 | $attrs = pop(@_); |
301 | } |
302 | my $query = ref $_[0] eq "HASH" ? { %{shift()} }: {@_}; |
303 | $query->{$_} = { 'like' => $query->{$_} } for keys %$query; |
304 | return $class->search($query, { %$attrs }); |
305 | } |
306 | |
bfab575a |
307 | =head2 slice($first, $last) |
ee38fa40 |
308 | |
bfab575a |
309 | Returns a subset of elements from the resultset. |
ee38fa40 |
310 | |
311 | =cut |
312 | |
89c0a5a2 |
313 | sub slice { |
314 | my ($self, $min, $max) = @_; |
315 | my $attrs = { %{ $self->{attrs} || {} } }; |
6aeb9185 |
316 | $attrs->{offset} ||= 0; |
317 | $attrs->{offset} += $min; |
89c0a5a2 |
318 | $attrs->{rows} = ($max ? ($max - $min + 1) : 1); |
701da8c4 |
319 | my $slice = (ref $self)->new($self->result_source, $attrs); |
89c0a5a2 |
320 | return (wantarray ? $slice->all : $slice); |
321 | } |
322 | |
87f0da6a |
323 | =head2 next |
ee38fa40 |
324 | |
a33df5d4 |
325 | Returns the next element in the resultset (C<undef> is there is none). |
326 | |
327 | Can be used to efficiently iterate over records in the resultset: |
328 | |
329 | my $rs = $schema->resultset('CD')->search({}); |
330 | while (my $cd = $rs->next) { |
331 | print $cd->title; |
332 | } |
ee38fa40 |
333 | |
334 | =cut |
335 | |
89c0a5a2 |
336 | sub next { |
337 | my ($self) = @_; |
73f58123 |
338 | my @row = $self->cursor->next; |
a953d8d9 |
339 | # warn Dumper(\@row); use Data::Dumper; |
89c0a5a2 |
340 | return unless (@row); |
c7ce65e6 |
341 | return $self->_construct_object(@row); |
342 | } |
343 | |
344 | sub _construct_object { |
345 | my ($self, @row) = @_; |
b3e8ac9b |
346 | my @as = @{ $self->{attrs}{as} }; |
976f3686 |
347 | #warn "@cols -> @row"; |
b3e8ac9b |
348 | my $info = [ {}, {} ]; |
349 | foreach my $as (@as) { |
350 | my $target = $info; |
351 | my @parts = split(/\./, $as); |
352 | my $col = pop(@parts); |
353 | foreach my $p (@parts) { |
354 | $target = $target->[1]->{$p} ||= []; |
c7ce65e6 |
355 | } |
b3e8ac9b |
356 | $target->[0]->{$col} = shift @row; |
c7ce65e6 |
357 | } |
b3e8ac9b |
358 | #use Data::Dumper; warn Dumper(\@as, $info); |
701da8c4 |
359 | my $new = $self->result_source->result_class->inflate_result( |
360 | $self->result_source, @$info); |
33ce49d6 |
361 | $new = $self->{attrs}{record_filter}->($new) |
362 | if exists $self->{attrs}{record_filter}; |
363 | return $new; |
89c0a5a2 |
364 | } |
365 | |
701da8c4 |
366 | =head2 result_source |
367 | |
368 | Returns a reference to the result source for this recordset. |
369 | |
370 | =cut |
371 | |
372 | |
bfab575a |
373 | =head2 count |
ee38fa40 |
374 | |
bfab575a |
375 | Performs an SQL C<COUNT> with the same query as the resultset was built |
6009260a |
376 | with to find the number of elements. If passed arguments, does a search |
377 | on the resultset and counts the results of that. |
ee38fa40 |
378 | |
bda4c2b8 |
379 | Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY> |
380 | using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do |
381 | not support C<DISTINCT> with multiple columns. If you are using such a |
382 | database, you should only use columns from the main table in your C<group_by> |
383 | clause. |
384 | |
ee38fa40 |
385 | =cut |
386 | |
89c0a5a2 |
387 | sub count { |
6009260a |
388 | my $self = shift; |
389 | return $self->search(@_)->count if @_ && defined $_[0]; |
6aeb9185 |
390 | unless (defined $self->{count}) { |
15c382be |
391 | my $group_by; |
392 | my $select = { 'count' => '*' }; |
393 | if( $group_by = delete $self->{attrs}{group_by} ) { |
394 | my @distinct = @$group_by; |
395 | # todo: try CONCAT for multi-column pk |
396 | my @pk = $self->result_source->primary_columns; |
397 | if( scalar(@pk) == 1 ) { |
398 | my $pk = shift(@pk); |
399 | my $alias = $self->{attrs}{alias}; |
400 | my $re = qr/^($alias\.)?$pk$/; |
401 | foreach my $column ( @$group_by ) { |
402 | if( $column =~ $re ) { |
403 | @distinct = ( $column ); |
404 | last; |
405 | } |
406 | } |
407 | } |
408 | |
409 | $select = { count => { 'distinct' => \@distinct } }; |
410 | #use Data::Dumper; die Dumper $select; |
411 | } |
412 | |
976f3686 |
413 | my $attrs = { %{ $self->{attrs} }, |
15c382be |
414 | select => $select, |
54540863 |
415 | as => [ 'count' ] }; |
ea20d0fd |
416 | # offset, order by and page are not needed to count. record_filter is cdbi |
417 | delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/; |
3c5b25c5 |
418 | |
701da8c4 |
419 | ($self->{count}) = (ref $self)->new($self->result_source, $attrs)->cursor->next; |
15c382be |
420 | $self->{attrs}{group_by} = $group_by; |
3c5b25c5 |
421 | } |
422 | return 0 unless $self->{count}; |
6aeb9185 |
423 | my $count = $self->{count}; |
424 | $count -= $self->{attrs}{offset} if $self->{attrs}{offset}; |
425 | $count = $self->{attrs}{rows} if |
426 | ($self->{attrs}{rows} && $self->{attrs}{rows} < $count); |
427 | return $count; |
89c0a5a2 |
428 | } |
429 | |
bfab575a |
430 | =head2 count_literal |
6009260a |
431 | |
a33df5d4 |
432 | Calls L</search_literal> with the passed arguments, then L</count>. |
6009260a |
433 | |
434 | =cut |
435 | |
436 | sub count_literal { shift->search_literal(@_)->count; } |
437 | |
bfab575a |
438 | =head2 all |
ee38fa40 |
439 | |
bfab575a |
440 | Returns all elements in the resultset. Called implictly if the resultset |
441 | is returned in list context. |
ee38fa40 |
442 | |
443 | =cut |
444 | |
89c0a5a2 |
445 | sub all { |
446 | my ($self) = @_; |
c7ce65e6 |
447 | return map { $self->_construct_object(@$_); } |
73f58123 |
448 | $self->cursor->all; |
89c0a5a2 |
449 | } |
450 | |
bfab575a |
451 | =head2 reset |
ee38fa40 |
452 | |
bfab575a |
453 | Resets the resultset's cursor, so you can iterate through the elements again. |
ee38fa40 |
454 | |
455 | =cut |
456 | |
89c0a5a2 |
457 | sub reset { |
458 | my ($self) = @_; |
73f58123 |
459 | $self->cursor->reset; |
89c0a5a2 |
460 | return $self; |
461 | } |
462 | |
bfab575a |
463 | =head2 first |
ee38fa40 |
464 | |
bfab575a |
465 | Resets the resultset and returns the first element. |
ee38fa40 |
466 | |
467 | =cut |
468 | |
89c0a5a2 |
469 | sub first { |
470 | return $_[0]->reset->next; |
471 | } |
472 | |
c01ab172 |
473 | =head2 update(\%values) |
474 | |
a33df5d4 |
475 | Sets the specified columns in the resultset to the supplied values. |
c01ab172 |
476 | |
477 | =cut |
478 | |
479 | sub update { |
480 | my ($self, $values) = @_; |
701da8c4 |
481 | $self->throw_exception("Values for update must be a hash") unless ref $values eq 'HASH'; |
482 | return $self->result_source->storage->update( |
483 | $self->result_source->from, $values, $self->{cond}); |
c01ab172 |
484 | } |
485 | |
486 | =head2 update_all(\%values) |
487 | |
a33df5d4 |
488 | Fetches all objects and updates them one at a time. Note that C<update_all> |
489 | will run cascade triggers while L</update> will not. |
c01ab172 |
490 | |
491 | =cut |
492 | |
493 | sub update_all { |
494 | my ($self, $values) = @_; |
701da8c4 |
495 | $self->throw_exception("Values for update must be a hash") unless ref $values eq 'HASH'; |
c01ab172 |
496 | foreach my $obj ($self->all) { |
497 | $obj->set_columns($values)->update; |
498 | } |
499 | return 1; |
500 | } |
501 | |
bfab575a |
502 | =head2 delete |
ee38fa40 |
503 | |
c01ab172 |
504 | Deletes the contents of the resultset from its result source. |
ee38fa40 |
505 | |
506 | =cut |
507 | |
28927b50 |
508 | sub delete { |
89c0a5a2 |
509 | my ($self) = @_; |
701da8c4 |
510 | $self->result_source->storage->delete($self->result_source->from, $self->{cond}); |
89c0a5a2 |
511 | return 1; |
512 | } |
513 | |
c01ab172 |
514 | =head2 delete_all |
515 | |
a33df5d4 |
516 | Fetches all objects and deletes them one at a time. Note that C<delete_all> |
517 | will run cascade triggers while L</delete> will not. |
c01ab172 |
518 | |
519 | =cut |
520 | |
521 | sub delete_all { |
522 | my ($self) = @_; |
523 | $_->delete for $self->all; |
524 | return 1; |
525 | } |
28927b50 |
526 | |
bfab575a |
527 | =head2 pager |
ee38fa40 |
528 | |
529 | Returns a L<Data::Page> object for the current resultset. Only makes |
a33df5d4 |
530 | sense for queries with a C<page> attribute. |
ee38fa40 |
531 | |
532 | =cut |
533 | |
3c5b25c5 |
534 | sub pager { |
535 | my ($self) = @_; |
536 | my $attrs = $self->{attrs}; |
701da8c4 |
537 | $self->throw_exception("Can't create pager for non-paged rs") unless $self->{page}; |
6aeb9185 |
538 | $attrs->{rows} ||= 10; |
539 | $self->count; |
540 | return $self->{pager} ||= Data::Page->new( |
93b004d3 |
541 | $self->{count}, $attrs->{rows}, $self->{page}); |
3c5b25c5 |
542 | } |
543 | |
bfab575a |
544 | =head2 page($page_num) |
ee38fa40 |
545 | |
bfab575a |
546 | Returns a new resultset for the specified page. |
ee38fa40 |
547 | |
548 | =cut |
549 | |
3c5b25c5 |
550 | sub page { |
551 | my ($self, $page) = @_; |
6aeb9185 |
552 | my $attrs = { %{$self->{attrs}} }; |
3c5b25c5 |
553 | $attrs->{page} = $page; |
701da8c4 |
554 | return (ref $self)->new($self->result_source, $attrs); |
fea3d045 |
555 | } |
556 | |
557 | =head2 new_result(\%vals) |
558 | |
87f0da6a |
559 | Creates a result in the resultset's result class. |
fea3d045 |
560 | |
561 | =cut |
562 | |
563 | sub new_result { |
564 | my ($self, $values) = @_; |
701da8c4 |
565 | $self->throw_exception( "new_result needs a hash" ) |
fea3d045 |
566 | unless (ref $values eq 'HASH'); |
701da8c4 |
567 | $self->throw_exception( "Can't abstract implicit construct, condition not a hash" ) |
fea3d045 |
568 | if ($self->{cond} && !(ref $self->{cond} eq 'HASH')); |
569 | my %new = %$values; |
570 | my $alias = $self->{attrs}{alias}; |
571 | foreach my $key (keys %{$self->{cond}||{}}) { |
572 | $new{$1} = $self->{cond}{$key} if ($key =~ m/^(?:$alias\.)?([^\.]+)$/); |
573 | } |
701da8c4 |
574 | my $obj = $self->result_source->result_class->new(\%new); |
575 | $obj->result_source($self->result_source) if $obj->can('result_source'); |
097d3227 |
576 | $obj; |
fea3d045 |
577 | } |
578 | |
579 | =head2 create(\%vals) |
580 | |
87f0da6a |
581 | Inserts a record into the resultset and returns the object. |
fea3d045 |
582 | |
a33df5d4 |
583 | Effectively a shortcut for C<< ->new_result(\%vals)->insert >>. |
fea3d045 |
584 | |
585 | =cut |
586 | |
587 | sub create { |
588 | my ($self, $attrs) = @_; |
701da8c4 |
589 | $self->throw_exception( "create needs a hashref" ) unless ref $attrs eq 'HASH'; |
fea3d045 |
590 | return $self->new_result($attrs)->insert; |
3c5b25c5 |
591 | } |
592 | |
87f0da6a |
593 | =head2 find_or_create(\%vals, \%attrs?) |
594 | |
595 | $class->find_or_create({ key => $val, ... }); |
c2b15ecc |
596 | |
c2b15ecc |
597 | Searches for a record matching the search condition; if it doesn't find one, |
cf7b40ed |
598 | creates one and returns that instead. |
87f0da6a |
599 | |
87f0da6a |
600 | my $cd = $schema->resultset('CD')->find_or_create({ |
601 | cdid => 5, |
602 | artist => 'Massive Attack', |
603 | title => 'Mezzanine', |
604 | year => 2005, |
605 | }); |
606 | |
607 | Also takes an optional C<key> attribute, to search by a specific key or unique |
608 | constraint. For example: |
609 | |
610 | my $cd = $schema->resultset('CD')->find_or_create( |
611 | { |
612 | artist => 'Massive Attack', |
613 | title => 'Mezzanine', |
614 | }, |
615 | { key => 'artist_title' } |
616 | ); |
617 | |
618 | See also L</find> and L</update_or_create>. |
619 | |
c2b15ecc |
620 | =cut |
621 | |
622 | sub find_or_create { |
623 | my $self = shift; |
87f0da6a |
624 | my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {}); |
625 | my $hash = ref $_[0] eq "HASH" ? shift : {@_}; |
626 | my $exists = $self->find($hash, $attrs); |
c2b15ecc |
627 | return defined($exists) ? $exists : $self->create($hash); |
628 | } |
629 | |
87f0da6a |
630 | =head2 update_or_create |
631 | |
632 | $class->update_or_create({ key => $val, ... }); |
633 | |
634 | First, search for an existing row matching one of the unique constraints |
635 | (including the primary key) on the source of this resultset. If a row is |
636 | found, update it with the other given column values. Otherwise, create a new |
637 | row. |
638 | |
639 | Takes an optional C<key> attribute to search on a specific unique constraint. |
640 | For example: |
641 | |
642 | # In your application |
643 | my $cd = $schema->resultset('CD')->update_or_create( |
644 | { |
645 | artist => 'Massive Attack', |
646 | title => 'Mezzanine', |
647 | year => 1998, |
648 | }, |
649 | { key => 'artist_title' } |
650 | ); |
651 | |
652 | If no C<key> is specified, it searches on all unique constraints defined on the |
653 | source, including the primary key. |
654 | |
655 | If the C<key> is specified as C<primary>, search only on the primary key. |
656 | |
a33df5d4 |
657 | See also L</find> and L</find_or_create>. |
658 | |
87f0da6a |
659 | =cut |
660 | |
661 | sub update_or_create { |
662 | my $self = shift; |
663 | |
664 | my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {}); |
665 | my $hash = ref $_[0] eq "HASH" ? shift : {@_}; |
666 | |
701da8c4 |
667 | my %unique_constraints = $self->result_source->unique_constraints; |
87f0da6a |
668 | my @constraint_names = (exists $attrs->{key} |
669 | ? ($attrs->{key}) |
670 | : keys %unique_constraints); |
671 | |
672 | my @unique_hashes; |
673 | foreach my $name (@constraint_names) { |
674 | my @unique_cols = @{ $unique_constraints{$name} }; |
675 | my %unique_hash = |
676 | map { $_ => $hash->{$_} } |
677 | grep { exists $hash->{$_} } |
678 | @unique_cols; |
679 | |
680 | push @unique_hashes, \%unique_hash |
681 | if (scalar keys %unique_hash == scalar @unique_cols); |
682 | } |
683 | |
684 | my $row; |
685 | if (@unique_hashes) { |
686 | $row = $self->search(\@unique_hashes, { rows => 1 })->first; |
687 | if ($row) { |
688 | $row->set_columns($hash); |
689 | $row->update; |
690 | } |
691 | } |
692 | |
693 | unless ($row) { |
694 | $row = $self->create($hash); |
695 | } |
696 | |
697 | return $row; |
698 | } |
699 | |
701da8c4 |
700 | =head2 throw_exception |
701 | |
702 | See Schema's throw_exception |
703 | |
704 | =cut |
705 | |
706 | sub throw_exception { |
707 | my $self=shift; |
708 | $self->result_source->schema->throw_exception(@_); |
709 | } |
710 | |
40dbc108 |
711 | =head1 ATTRIBUTES |
076652e8 |
712 | |
a33df5d4 |
713 | The resultset takes various attributes that modify its behavior. Here's an |
714 | overview of them: |
bfab575a |
715 | |
716 | =head2 order_by |
076652e8 |
717 | |
a33df5d4 |
718 | Which column(s) to order the results by. This is currently passed through |
719 | directly to SQL, so you can give e.g. C<foo DESC> for a descending order. |
076652e8 |
720 | |
976f3686 |
721 | =head2 cols (arrayref) |
722 | |
a33df5d4 |
723 | Shortcut to request a particular set of columns to be retrieved. Adds |
724 | C<me.> onto the start of any column without a C<.> in it and sets C<select> |
725 | from that, then auto-populates C<as> from C<select> as normal. |
976f3686 |
726 | |
5ac6a044 |
727 | =head2 include_columns (arrayref) |
728 | |
729 | Shortcut to include additional columns in the returned results - for example |
730 | |
731 | { include_columns => ['foo.name'], join => ['foo'] } |
732 | |
733 | would add a 'name' column to the information passed to object inflation |
734 | |
976f3686 |
735 | =head2 select (arrayref) |
736 | |
4a28c340 |
737 | Indicates which columns should be selected from the storage. You can use |
738 | column names, or in the case of RDBMS back ends, function or stored procedure |
739 | names: |
740 | |
741 | $rs = $schema->resultset('Foo')->search( |
742 | {}, |
743 | { |
cf7b40ed |
744 | select => [ |
4a28c340 |
745 | 'column_name', |
746 | { count => 'column_to_count' }, |
747 | { sum => 'column_to_sum' } |
cf7b40ed |
748 | ] |
4a28c340 |
749 | } |
750 | ); |
751 | |
752 | When you use function/stored procedure names and do not supply an C<as> |
753 | attribute, the column names returned are storage-dependent. E.g. MySQL would |
754 | return a column named C<count(column_to_count)> in the above example. |
976f3686 |
755 | |
756 | =head2 as (arrayref) |
076652e8 |
757 | |
4a28c340 |
758 | Indicates column names for object inflation. This is used in conjunction with |
759 | C<select>, usually when C<select> contains one or more function or stored |
760 | procedure names: |
761 | |
762 | $rs = $schema->resultset('Foo')->search( |
763 | {}, |
764 | { |
cf7b40ed |
765 | select => [ |
4a28c340 |
766 | 'column1', |
767 | { count => 'column2' } |
cf7b40ed |
768 | ], |
4a28c340 |
769 | as => [qw/ column1 column2_count /] |
770 | } |
771 | ); |
772 | |
773 | my $foo = $rs->first(); # get the first Foo |
774 | |
775 | If the object against which the search is performed already has an accessor |
776 | matching a column name specified in C<as>, the value can be retrieved using |
777 | the accessor as normal: |
778 | |
779 | my $column1 = $foo->column1(); |
780 | |
781 | If on the other hand an accessor does not exist in the object, you need to |
782 | use C<get_column> instead: |
783 | |
784 | my $column2_count = $foo->get_column('column2_count'); |
785 | |
786 | You can create your own accessors if required - see |
787 | L<DBIx::Class::Manual::Cookbook> for details. |
ee38fa40 |
788 | |
bfab575a |
789 | =head2 join |
ee38fa40 |
790 | |
a33df5d4 |
791 | Contains a list of relationships that should be joined for this query. For |
792 | example: |
793 | |
794 | # Get CDs by Nine Inch Nails |
795 | my $rs = $schema->resultset('CD')->search( |
796 | { 'artist.name' => 'Nine Inch Nails' }, |
797 | { join => 'artist' } |
798 | ); |
799 | |
800 | Can also contain a hash reference to refer to the other relation's relations. |
801 | For example: |
802 | |
803 | package MyApp::Schema::Track; |
804 | use base qw/DBIx::Class/; |
805 | __PACKAGE__->table('track'); |
806 | __PACKAGE__->add_columns(qw/trackid cd position title/); |
807 | __PACKAGE__->set_primary_key('trackid'); |
808 | __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD'); |
809 | 1; |
810 | |
811 | # In your application |
812 | my $rs = $schema->resultset('Artist')->search( |
813 | { 'track.title' => 'Teardrop' }, |
814 | { |
815 | join => { cd => 'track' }, |
816 | order_by => 'artist.name', |
817 | } |
818 | ); |
819 | |
ae1c90a1 |
820 | If you want to fetch columns from related tables as well, see C<prefetch> |
821 | below. |
ee38fa40 |
822 | |
ae1c90a1 |
823 | =head2 prefetch arrayref/hashref |
ee38fa40 |
824 | |
ae1c90a1 |
825 | Contains one or more relationships that should be fetched along with the main |
bfab575a |
826 | query (when they are accessed afterwards they will have already been |
a33df5d4 |
827 | "prefetched"). This is useful for when you know you will need the related |
ae1c90a1 |
828 | objects, because it saves at least one query: |
829 | |
830 | my $rs = $schema->resultset('Tag')->search( |
831 | {}, |
832 | { |
833 | prefetch => { |
834 | cd => 'artist' |
835 | } |
836 | } |
837 | ); |
838 | |
839 | The initial search results in SQL like the following: |
840 | |
841 | SELECT tag.*, cd.*, artist.* FROM tag |
842 | JOIN cd ON tag.cd = cd.cdid |
843 | JOIN artist ON cd.artist = artist.artistid |
844 | |
845 | L<DBIx::Class> has no need to go back to the database when we access the |
846 | C<cd> or C<artist> relationships, which saves us two SQL statements in this |
847 | case. |
848 | |
849 | Any prefetched relationship will be joined automatically, so there is no need |
850 | for a C<join> attribute in the above search. |
851 | |
852 | C<prefetch> can be used with the following relationship types: C<belongs_to>, |
853 | C<has_one>. |
ee38fa40 |
854 | |
4a28c340 |
855 | =head2 from (arrayref) |
ee38fa40 |
856 | |
4a28c340 |
857 | The C<from> attribute gives you manual control over the C<FROM> clause of SQL |
858 | statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN> |
859 | clauses. |
ee38fa40 |
860 | |
a33df5d4 |
861 | NOTE: Use this on your own risk. This allows you to shoot off your foot! |
4a28c340 |
862 | C<join> will usually do what you need and it is strongly recommended that you |
863 | avoid using C<from> unless you cannot achieve the desired result using C<join>. |
864 | |
865 | In simple terms, C<from> works as follows: |
866 | |
867 | [ |
868 | { <alias> => <table>, -join-type => 'inner|left|right' } |
869 | [] # nested JOIN (optional) |
870 | { <table.column> = <foreign_table.foreign_key> } |
871 | ] |
872 | |
873 | JOIN |
874 | <alias> <table> |
875 | [JOIN ...] |
876 | ON <table.column> = <foreign_table.foreign_key> |
877 | |
878 | An easy way to follow the examples below is to remember the following: |
879 | |
880 | Anything inside "[]" is a JOIN |
881 | Anything inside "{}" is a condition for the enclosing JOIN |
882 | |
883 | The following examples utilize a "person" table in a family tree application. |
884 | In order to express parent->child relationships, this table is self-joined: |
885 | |
886 | # Person->belongs_to('father' => 'Person'); |
887 | # Person->belongs_to('mother' => 'Person'); |
888 | |
889 | C<from> can be used to nest joins. Here we return all children with a father, |
890 | then search against all mothers of those children: |
891 | |
892 | $rs = $schema->resultset('Person')->search( |
893 | {}, |
894 | { |
895 | alias => 'mother', # alias columns in accordance with "from" |
896 | from => [ |
897 | { mother => 'person' }, |
898 | [ |
899 | [ |
900 | { child => 'person' }, |
901 | [ |
902 | { father => 'person' }, |
903 | { 'father.person_id' => 'child.father_id' } |
904 | ] |
905 | ], |
906 | { 'mother.person_id' => 'child.mother_id' } |
907 | ], |
908 | ] |
909 | }, |
910 | ); |
911 | |
912 | # Equivalent SQL: |
913 | # SELECT mother.* FROM person mother |
914 | # JOIN ( |
915 | # person child |
916 | # JOIN person father |
917 | # ON ( father.person_id = child.father_id ) |
918 | # ) |
919 | # ON ( mother.person_id = child.mother_id ) |
920 | |
921 | The type of any join can be controlled manually. To search against only people |
922 | with a father in the person table, we could explicitly use C<INNER JOIN>: |
923 | |
924 | $rs = $schema->resultset('Person')->search( |
925 | {}, |
926 | { |
927 | alias => 'child', # alias columns in accordance with "from" |
928 | from => [ |
929 | { child => 'person' }, |
930 | [ |
931 | { father => 'person', -join-type => 'inner' }, |
932 | { 'father.id' => 'child.father_id' } |
933 | ], |
934 | ] |
935 | }, |
936 | ); |
937 | |
938 | # Equivalent SQL: |
939 | # SELECT child.* FROM person child |
940 | # INNER JOIN person father ON child.father_id = father.id |
ee38fa40 |
941 | |
bfab575a |
942 | =head2 page |
076652e8 |
943 | |
a33df5d4 |
944 | For a paged resultset, specifies which page to retrieve. Leave unset |
bfab575a |
945 | for an unpaged resultset. |
076652e8 |
946 | |
bfab575a |
947 | =head2 rows |
076652e8 |
948 | |
4a28c340 |
949 | For a paged resultset, how many rows per page: |
950 | |
951 | rows => 10 |
952 | |
953 | Can also be used to simulate an SQL C<LIMIT>. |
076652e8 |
954 | |
a33df5d4 |
955 | =head2 group_by (arrayref) |
54540863 |
956 | |
bda4c2b8 |
957 | A arrayref of columns to group by. Can include columns of joined tables. |
54540863 |
958 | |
675ce4a6 |
959 | group_by => [qw/ column1 column2 ... /] |
960 | |
54540863 |
961 | =head2 distinct |
962 | |
a33df5d4 |
963 | Set to 1 to group by all columns. |
964 | |
965 | For more examples of using these attributes, see |
966 | L<DBIx::Class::Manual::Cookbook>. |
54540863 |
967 | |
bfab575a |
968 | =cut |
076652e8 |
969 | |
89c0a5a2 |
970 | 1; |