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