Commit | Line | Data |
89c0a5a2 |
1 | package DBIx::Class::ResultSet; |
2 | |
3 | use strict; |
4 | use warnings; |
5 | use overload |
ebaefbc2 |
6 | '0+' => \&count, |
a910dc57 |
7 | 'bool' => sub { 1; }, |
89c0a5a2 |
8 | fallback => 1; |
3c5b25c5 |
9 | use Data::Page; |
ea20d0fd |
10 | use Storable; |
bcd26419 |
11 | use Scalar::Util qw/weaken/; |
89c0a5a2 |
12 | |
701da8c4 |
13 | use base qw/DBIx::Class/; |
14 | __PACKAGE__->load_components(qw/AccessorGroup/); |
a50bcd52 |
15 | __PACKAGE__->mk_group_accessors('simple' => qw/result_source result_class/); |
701da8c4 |
16 | |
ee38fa40 |
17 | =head1 NAME |
18 | |
bfab575a |
19 | DBIx::Class::ResultSet - Responsible for fetching and creating resultset. |
ee38fa40 |
20 | |
bfab575a |
21 | =head1 SYNOPSIS |
ee38fa40 |
22 | |
a33df5d4 |
23 | my $rs = $schema->resultset('User')->search(registered => 1); |
24d67825 |
24 | my @rows = $schema->resultset('CD')->search(year => 2005); |
ee38fa40 |
25 | |
26 | =head1 DESCRIPTION |
27 | |
bfab575a |
28 | The resultset is also known as an iterator. It is responsible for handling |
a33df5d4 |
29 | queries that may return an arbitrary number of rows, e.g. via L</search> |
bfab575a |
30 | or a C<has_many> relationship. |
ee38fa40 |
31 | |
a33df5d4 |
32 | In the examples below, the following table classes are used: |
33 | |
34 | package MyApp::Schema::Artist; |
35 | use base qw/DBIx::Class/; |
f4409169 |
36 | __PACKAGE__->load_components(qw/Core/); |
a33df5d4 |
37 | __PACKAGE__->table('artist'); |
38 | __PACKAGE__->add_columns(qw/artistid name/); |
39 | __PACKAGE__->set_primary_key('artistid'); |
40 | __PACKAGE__->has_many(cds => 'MyApp::Schema::CD'); |
41 | 1; |
42 | |
43 | package MyApp::Schema::CD; |
44 | use base qw/DBIx::Class/; |
f4409169 |
45 | __PACKAGE__->load_components(qw/Core/); |
46 | __PACKAGE__->table('cd'); |
a33df5d4 |
47 | __PACKAGE__->add_columns(qw/cdid artist title year/); |
48 | __PACKAGE__->set_primary_key('cdid'); |
49 | __PACKAGE__->belongs_to(artist => 'MyApp::Schema::Artist'); |
50 | 1; |
51 | |
ee38fa40 |
52 | =head1 METHODS |
53 | |
87c4e602 |
54 | =head2 new |
55 | |
56 | =head3 Arguments: ($source, \%$attrs) |
ee38fa40 |
57 | |
a33df5d4 |
58 | The resultset constructor. Takes a source object (usually a |
aa1088bf |
59 | L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see |
60 | L</ATTRIBUTES> below). Does not perform any queries -- these are |
61 | executed as needed by the other methods. |
a33df5d4 |
62 | |
63 | Generally you won't need to construct a resultset manually. You'll |
64 | automatically get one from e.g. a L</search> called in scalar context: |
65 | |
66 | my $rs = $schema->resultset('CD')->search({ title => '100th Window' }); |
ee38fa40 |
67 | |
68 | =cut |
69 | |
89c0a5a2 |
70 | sub new { |
fea3d045 |
71 | my $class = shift; |
f9db5527 |
72 | return $class->new_result(@_) if ref $class; |
5e8b1b2a |
73 | |
fea3d045 |
74 | my ($source, $attrs) = @_; |
bcd26419 |
75 | weaken $source; |
ea20d0fd |
76 | $attrs = Storable::dclone($attrs || {}); # { %{ $attrs || {} } }; |
bcd26419 |
77 | #use Data::Dumper; warn Dumper($attrs); |
6aeb9185 |
78 | my $alias = ($attrs->{alias} ||= 'me'); |
5e8b1b2a |
79 | |
80 | $attrs->{columns} ||= delete $attrs->{cols} if $attrs->{cols}; |
1c258fc1 |
81 | delete $attrs->{as} if $attrs->{columns}; |
5e8b1b2a |
82 | $attrs->{columns} ||= [ $source->columns ] unless $attrs->{select}; |
aa1088bf |
83 | $attrs->{select} = [ |
84 | map { m/\./ ? $_ : "${alias}.$_" } @{delete $attrs->{columns}} |
85 | ] if $attrs->{columns}; |
86 | $attrs->{as} ||= [ |
87 | map { m/^\Q$alias.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}} |
88 | ]; |
5ac6a044 |
89 | if (my $include = delete $attrs->{include_columns}) { |
90 | push(@{$attrs->{select}}, @$include); |
223aea40 |
91 | push(@{$attrs->{as}}, map { m/([^.]+)$/; $1; } @$include); |
5ac6a044 |
92 | } |
976f3686 |
93 | #use Data::Dumper; warn Dumper(@{$attrs}{qw/select as/}); |
5e8b1b2a |
94 | |
fea3d045 |
95 | $attrs->{from} ||= [ { $alias => $source->from } ]; |
8fab5eef |
96 | $attrs->{seen_join} ||= {}; |
5e8b1b2a |
97 | my %seen; |
b52e9bf8 |
98 | if (my $join = delete $attrs->{join}) { |
5e8b1b2a |
99 | foreach my $j (ref $join eq 'ARRAY' ? @$join : ($join)) { |
c7ce65e6 |
100 | if (ref $j eq 'HASH') { |
101 | $seen{$_} = 1 foreach keys %$j; |
102 | } else { |
103 | $seen{$j} = 1; |
104 | } |
105 | } |
aa1088bf |
106 | push(@{$attrs->{from}}, $source->resolve_join( |
107 | $join, $attrs->{alias}, $attrs->{seen_join}) |
108 | ); |
c7ce65e6 |
109 | } |
5e8b1b2a |
110 | |
54540863 |
111 | $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct}; |
aa1088bf |
112 | $attrs->{order_by} = [ $attrs->{order_by} ] if |
113 | $attrs->{order_by} and !ref($attrs->{order_by}); |
a86b1efe |
114 | $attrs->{order_by} ||= []; |
115 | |
555af3d9 |
116 | my $collapse = $attrs->{collapse} || {}; |
b3e8ac9b |
117 | if (my $prefetch = delete $attrs->{prefetch}) { |
0f66a01b |
118 | my @pre_order; |
5e8b1b2a |
119 | foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) { |
120 | if ( ref $p eq 'HASH' ) { |
b3e8ac9b |
121 | foreach my $key (keys %$p) { |
122 | push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias})) |
123 | unless $seen{$key}; |
124 | } |
5e8b1b2a |
125 | } else { |
b3e8ac9b |
126 | push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias})) |
127 | unless $seen{$p}; |
128 | } |
a86b1efe |
129 | my @prefetch = $source->resolve_prefetch( |
0f66a01b |
130 | $p, $attrs->{alias}, {}, \@pre_order, $collapse); |
489709af |
131 | push(@{$attrs->{select}}, map { $_->[0] } @prefetch); |
132 | push(@{$attrs->{as}}, map { $_->[1] } @prefetch); |
b3e8ac9b |
133 | } |
0f66a01b |
134 | push(@{$attrs->{order_by}}, @pre_order); |
fef5d100 |
135 | } |
555af3d9 |
136 | $attrs->{collapse} = $collapse; |
5e8b1b2a |
137 | # use Data::Dumper; warn Dumper($collapse) if keys %{$collapse}; |
555af3d9 |
138 | |
6aeb9185 |
139 | if ($attrs->{page}) { |
140 | $attrs->{rows} ||= 10; |
141 | $attrs->{offset} ||= 0; |
142 | $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1)); |
143 | } |
0f66a01b |
144 | |
5e8b1b2a |
145 | bless { |
701da8c4 |
146 | result_source => $source, |
a50bcd52 |
147 | result_class => $attrs->{result_class} || $source->result_class, |
89c0a5a2 |
148 | cond => $attrs->{where}, |
0a3c5b43 |
149 | from => $attrs->{from}, |
0f66a01b |
150 | collapse => $collapse, |
3c5b25c5 |
151 | count => undef, |
93b004d3 |
152 | page => delete $attrs->{page}, |
3c5b25c5 |
153 | pager => undef, |
5e8b1b2a |
154 | attrs => $attrs |
155 | }, $class; |
89c0a5a2 |
156 | } |
157 | |
bfab575a |
158 | =head2 search |
0a3c5b43 |
159 | |
24d67825 |
160 | my @cds = $rs->search({ year => 2001 }); # "... WHERE year = 2001" |
161 | my $new_rs = $rs->search({ year => 2005 }); |
87f0da6a |
162 | |
6009260a |
163 | If you need to pass in additional attributes but no additional condition, |
5e8b1b2a |
164 | call it as C<search(undef, \%attrs);>. |
87f0da6a |
165 | |
24d67825 |
166 | # "SELECT name, artistid FROM $artist_table" |
167 | my @all_artists = $schema->resultset('Artist')->search(undef, { |
168 | columns => [qw/name artistid/], |
169 | }); |
0a3c5b43 |
170 | |
171 | =cut |
172 | |
173 | sub search { |
174 | my $self = shift; |
175 | |
ff7bb7a1 |
176 | my $rs; |
177 | if( @_ ) { |
178 | |
179 | my $attrs = { %{$self->{attrs}} }; |
8839560b |
180 | my $having = delete $attrs->{having}; |
223aea40 |
181 | $attrs = { %$attrs, %{ pop(@_) } } if @_ > 1 and ref $_[$#_] eq 'HASH'; |
6009260a |
182 | |
3e0e9e27 |
183 | my $where = (@_ |
184 | ? ((@_ == 1 || ref $_[0] eq "HASH") |
185 | ? shift |
186 | : ((@_ % 2) |
187 | ? $self->throw_exception( |
188 | "Odd number of arguments to search") |
189 | : {@_})) |
190 | : undef()); |
ff7bb7a1 |
191 | if (defined $where) { |
223aea40 |
192 | $attrs->{where} = (defined $attrs->{where} |
ad3d2d7c |
193 | ? { '-and' => |
194 | [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ } |
195 | $where, $attrs->{where} ] } |
0a3c5b43 |
196 | : $where); |
ff7bb7a1 |
197 | } |
0a3c5b43 |
198 | |
8839560b |
199 | if (defined $having) { |
223aea40 |
200 | $attrs->{having} = (defined $attrs->{having} |
8839560b |
201 | ? { '-and' => |
202 | [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ } |
203 | $having, $attrs->{having} ] } |
204 | : $having); |
8839560b |
205 | } |
206 | |
ff7bb7a1 |
207 | $rs = (ref $self)->new($self->result_source, $attrs); |
208 | } |
209 | else { |
210 | $rs = $self; |
223aea40 |
211 | $rs->reset; |
ff7bb7a1 |
212 | } |
0a3c5b43 |
213 | return (wantarray ? $rs->all : $rs); |
214 | } |
215 | |
87f0da6a |
216 | =head2 search_literal |
217 | |
6009260a |
218 | my @obj = $rs->search_literal($literal_where_cond, @bind); |
219 | my $new_rs = $rs->search_literal($literal_where_cond, @bind); |
220 | |
221 | Pass a literal chunk of SQL to be added to the conditional part of the |
87f0da6a |
222 | resultset. |
6009260a |
223 | |
bfab575a |
224 | =cut |
fd9f5466 |
225 | |
6009260a |
226 | sub search_literal { |
227 | my ($self, $cond, @vals) = @_; |
228 | my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {}); |
229 | $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ]; |
230 | return $self->search(\$cond, $attrs); |
231 | } |
0a3c5b43 |
232 | |
87c4e602 |
233 | =head2 find |
234 | |
235 | =head3 Arguments: (@colvalues) | (\%cols, \%attrs?) |
87f0da6a |
236 | |
237 | Finds a row based on its primary key or unique constraint. For example: |
238 | |
87f0da6a |
239 | my $cd = $schema->resultset('CD')->find(5); |
240 | |
241 | Also takes an optional C<key> attribute, to search by a specific key or unique |
242 | constraint. For example: |
243 | |
fd9f5466 |
244 | my $cd = $schema->resultset('CD')->find( |
87f0da6a |
245 | { |
246 | artist => 'Massive Attack', |
247 | title => 'Mezzanine', |
248 | }, |
249 | { key => 'artist_title' } |
250 | ); |
251 | |
a33df5d4 |
252 | See also L</find_or_create> and L</update_or_create>. |
253 | |
87f0da6a |
254 | =cut |
716b3d29 |
255 | |
256 | sub find { |
257 | my ($self, @vals) = @_; |
258 | my $attrs = (@vals > 1 && ref $vals[$#vals] eq 'HASH' ? pop(@vals) : {}); |
87f0da6a |
259 | |
701da8c4 |
260 | my @cols = $self->result_source->primary_columns; |
87f0da6a |
261 | if (exists $attrs->{key}) { |
701da8c4 |
262 | my %uniq = $self->result_source->unique_constraints; |
aa1088bf |
263 | $self->throw_exception( |
264 | "Unknown key $attrs->{key} on '" . $self->result_source->name . "'" |
265 | ) unless exists $uniq{$attrs->{key}}; |
87f0da6a |
266 | @cols = @{ $uniq{$attrs->{key}} }; |
267 | } |
268 | #use Data::Dumper; warn Dumper($attrs, @vals, @cols); |
aa1088bf |
269 | $self->throw_exception( |
270 | "Can't find unless a primary key or unique constraint is defined" |
271 | ) unless @cols; |
87f0da6a |
272 | |
716b3d29 |
273 | my $query; |
274 | if (ref $vals[0] eq 'HASH') { |
01bc091e |
275 | $query = { %{$vals[0]} }; |
87f0da6a |
276 | } elsif (@cols == @vals) { |
716b3d29 |
277 | $query = {}; |
87f0da6a |
278 | @{$query}{@cols} = @vals; |
716b3d29 |
279 | } else { |
280 | $query = {@vals}; |
281 | } |
223aea40 |
282 | foreach my $key (grep { ! m/\./ } keys %$query) { |
283 | $query->{"$self->{attrs}{alias}.$key"} = delete $query->{$key}; |
01bc091e |
284 | } |
716b3d29 |
285 | #warn Dumper($query); |
8389d433 |
286 | |
287 | if (keys %$attrs) { |
288 | my $rs = $self->search($query,$attrs); |
289 | return keys %{$rs->{collapse}} ? $rs->next : $rs->single; |
290 | } else { |
aa1088bf |
291 | return keys %{$self->{collapse}} ? |
292 | $self->search($query)->next : |
293 | $self->single($query); |
8389d433 |
294 | } |
716b3d29 |
295 | } |
296 | |
b52e9bf8 |
297 | =head2 search_related |
298 | |
299 | $rs->search_related('relname', $cond?, $attrs?); |
300 | |
a33df5d4 |
301 | Search the specified relationship. Optionally specify a condition for matching |
302 | records. |
303 | |
b52e9bf8 |
304 | =cut |
305 | |
6aeb9185 |
306 | sub search_related { |
64acc2bc |
307 | return shift->related_resultset(shift)->search(@_); |
6aeb9185 |
308 | } |
b52e9bf8 |
309 | |
bfab575a |
310 | =head2 cursor |
ee38fa40 |
311 | |
bfab575a |
312 | Returns a storage-driven cursor to the given resultset. |
ee38fa40 |
313 | |
314 | =cut |
315 | |
73f58123 |
316 | sub cursor { |
317 | my ($self) = @_; |
223aea40 |
318 | my $attrs = { %{$self->{attrs}} }; |
73f58123 |
319 | return $self->{cursor} |
701da8c4 |
320 | ||= $self->result_source->storage->select($self->{from}, $attrs->{select}, |
73f58123 |
321 | $attrs->{where},$attrs); |
322 | } |
323 | |
a04ab285 |
324 | =head2 single |
325 | |
326 | Inflates the first result without creating a cursor |
327 | |
328 | =cut |
329 | |
330 | sub single { |
223aea40 |
331 | my ($self, $where) = @_; |
332 | my $attrs = { %{$self->{attrs}} }; |
333 | if ($where) { |
a04ab285 |
334 | if (defined $attrs->{where}) { |
335 | $attrs->{where} = { |
223aea40 |
336 | '-and' => |
337 | [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ } |
338 | $where, delete $attrs->{where} ] |
a04ab285 |
339 | }; |
340 | } else { |
223aea40 |
341 | $attrs->{where} = $where; |
a04ab285 |
342 | } |
343 | } |
344 | my @data = $self->result_source->storage->select_single( |
345 | $self->{from}, $attrs->{select}, |
346 | $attrs->{where},$attrs); |
347 | return (@data ? $self->_construct_object(@data) : ()); |
348 | } |
349 | |
350 | |
87f0da6a |
351 | =head2 search_like |
352 | |
a33df5d4 |
353 | Perform a search, but use C<LIKE> instead of equality as the condition. Note |
354 | that this is simply a convenience method; you most likely want to use |
355 | L</search> with specific operators. |
356 | |
357 | For more information, see L<DBIx::Class::Manual::Cookbook>. |
87f0da6a |
358 | |
359 | =cut |
58a4bd18 |
360 | |
361 | sub search_like { |
223aea40 |
362 | my $class = shift; |
363 | my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {}); |
364 | my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_}; |
58a4bd18 |
365 | $query->{$_} = { 'like' => $query->{$_} } for keys %$query; |
366 | return $class->search($query, { %$attrs }); |
367 | } |
368 | |
87c4e602 |
369 | =head2 slice |
370 | |
371 | =head3 Arguments: ($first, $last) |
ee38fa40 |
372 | |
bfab575a |
373 | Returns a subset of elements from the resultset. |
ee38fa40 |
374 | |
375 | =cut |
376 | |
89c0a5a2 |
377 | sub slice { |
378 | my ($self, $min, $max) = @_; |
379 | my $attrs = { %{ $self->{attrs} || {} } }; |
6aeb9185 |
380 | $attrs->{offset} ||= 0; |
381 | $attrs->{offset} += $min; |
89c0a5a2 |
382 | $attrs->{rows} = ($max ? ($max - $min + 1) : 1); |
701da8c4 |
383 | my $slice = (ref $self)->new($self->result_source, $attrs); |
89c0a5a2 |
384 | return (wantarray ? $slice->all : $slice); |
385 | } |
386 | |
87f0da6a |
387 | =head2 next |
ee38fa40 |
388 | |
a33df5d4 |
389 | Returns the next element in the resultset (C<undef> is there is none). |
390 | |
391 | Can be used to efficiently iterate over records in the resultset: |
392 | |
5e8b1b2a |
393 | my $rs = $schema->resultset('CD')->search; |
a33df5d4 |
394 | while (my $cd = $rs->next) { |
395 | print $cd->title; |
396 | } |
ee38fa40 |
397 | |
398 | =cut |
399 | |
89c0a5a2 |
400 | sub next { |
401 | my ($self) = @_; |
223aea40 |
402 | if (@{$self->{all_cache} || []}) { |
64acc2bc |
403 | $self->{all_cache_position} ||= 0; |
223aea40 |
404 | return $self->{all_cache}->[$self->{all_cache_position}++]; |
64acc2bc |
405 | } |
3e0e9e27 |
406 | if ($self->{attrs}{cache}) { |
0f66a01b |
407 | $self->{all_cache_position} = 1; |
3e0e9e27 |
408 | return ($self->all)[0]; |
409 | } |
aa1088bf |
410 | my @row = (exists $self->{stashed_row} ? |
411 | @{delete $self->{stashed_row}} : |
412 | $self->cursor->next |
413 | ); |
a953d8d9 |
414 | # warn Dumper(\@row); use Data::Dumper; |
89c0a5a2 |
415 | return unless (@row); |
c7ce65e6 |
416 | return $self->_construct_object(@row); |
417 | } |
418 | |
419 | sub _construct_object { |
420 | my ($self, @row) = @_; |
b3e8ac9b |
421 | my @as = @{ $self->{attrs}{as} }; |
223aea40 |
422 | |
0f66a01b |
423 | my $info = $self->_collapse_result(\@as, \@row); |
223aea40 |
424 | |
a50bcd52 |
425 | my $new = $self->result_class->inflate_result($self->result_source, @$info); |
223aea40 |
426 | |
33ce49d6 |
427 | $new = $self->{attrs}{record_filter}->($new) |
428 | if exists $self->{attrs}{record_filter}; |
429 | return $new; |
89c0a5a2 |
430 | } |
431 | |
0f66a01b |
432 | sub _collapse_result { |
433 | my ($self, $as, $row, $prefix) = @_; |
434 | |
435 | my %const; |
436 | |
437 | my @copy = @$row; |
5a5bec6c |
438 | foreach my $this_as (@$as) { |
439 | my $val = shift @copy; |
440 | if (defined $prefix) { |
441 | if ($this_as =~ m/^\Q${prefix}.\E(.+)$/) { |
442 | my $remain = $1; |
223aea40 |
443 | $remain =~ /^(?:(.*)\.)?([^.]+)$/; |
5a5bec6c |
444 | $const{$1||''}{$2} = $val; |
445 | } |
446 | } else { |
223aea40 |
447 | $this_as =~ /^(?:(.*)\.)?([^.]+)$/; |
5a5bec6c |
448 | $const{$1||''}{$2} = $val; |
0f66a01b |
449 | } |
0f66a01b |
450 | } |
451 | |
0f66a01b |
452 | my $info = [ {}, {} ]; |
453 | foreach my $key (keys %const) { |
454 | if (length $key) { |
455 | my $target = $info; |
456 | my @parts = split(/\./, $key); |
457 | foreach my $p (@parts) { |
458 | $target = $target->[1]->{$p} ||= []; |
459 | } |
460 | $target->[0] = $const{$key}; |
461 | } else { |
462 | $info->[0] = $const{$key}; |
463 | } |
464 | } |
465 | |
aa1088bf |
466 | my @collapse; |
467 | if (defined $prefix) { |
468 | @collapse = map { |
469 | m/^\Q${prefix}.\E(.+)$/ ? ($1) : () |
470 | } keys %{$self->{collapse}}) |
471 | } else { |
472 | @collapse = keys %{$self->{collapse}}; |
473 | ); |
474 | |
5a5bec6c |
475 | if (@collapse) { |
476 | my ($c) = sort { length $a <=> length $b } @collapse; |
0f66a01b |
477 | my $target = $info; |
0f66a01b |
478 | foreach my $p (split(/\./, $c)) { |
5a5bec6c |
479 | $target = $target->[1]->{$p} ||= []; |
0f66a01b |
480 | } |
5a5bec6c |
481 | my $c_prefix = (defined($prefix) ? "${prefix}.${c}" : $c); |
482 | my @co_key = @{$self->{collapse}{$c_prefix}}; |
0f66a01b |
483 | my %co_check = map { ($_, $target->[0]->{$_}); } @co_key; |
5a5bec6c |
484 | my $tree = $self->_collapse_result($as, $row, $c_prefix); |
0f66a01b |
485 | my (@final, @raw); |
5a5bec6c |
486 | while ( !(grep { |
aa1088bf |
487 | !defined($tree->[0]->{$_}) || |
488 | $co_check{$_} ne $tree->[0]->{$_} |
5a5bec6c |
489 | } @co_key) ) { |
0f66a01b |
490 | push(@final, $tree); |
491 | last unless (@raw = $self->cursor->next); |
492 | $row = $self->{stashed_row} = \@raw; |
5a5bec6c |
493 | $tree = $self->_collapse_result($as, $row, $c_prefix); |
494 | #warn Data::Dumper::Dumper($tree, $row); |
0f66a01b |
495 | } |
223aea40 |
496 | @$target = @final; |
0f66a01b |
497 | } |
498 | |
0f66a01b |
499 | return $info; |
500 | } |
501 | |
87c4e602 |
502 | =head2 result_source |
701da8c4 |
503 | |
504 | Returns a reference to the result source for this recordset. |
505 | |
506 | =cut |
507 | |
508 | |
bfab575a |
509 | =head2 count |
ee38fa40 |
510 | |
bfab575a |
511 | Performs an SQL C<COUNT> with the same query as the resultset was built |
6009260a |
512 | with to find the number of elements. If passed arguments, does a search |
513 | on the resultset and counts the results of that. |
ee38fa40 |
514 | |
bda4c2b8 |
515 | Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY> |
516 | using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do |
517 | not support C<DISTINCT> with multiple columns. If you are using such a |
518 | database, you should only use columns from the main table in your C<group_by> |
519 | clause. |
520 | |
ee38fa40 |
521 | =cut |
522 | |
89c0a5a2 |
523 | sub count { |
6009260a |
524 | my $self = shift; |
223aea40 |
525 | return $self->search(@_)->count if @_ and defined $_[0]; |
84e3c114 |
526 | return scalar @{ $self->get_cache } if @{ $self->get_cache }; |
15c382be |
527 | |
84e3c114 |
528 | my $count = $self->_count; |
529 | return 0 unless $count; |
15c382be |
530 | |
6aeb9185 |
531 | $count -= $self->{attrs}{offset} if $self->{attrs}{offset}; |
532 | $count = $self->{attrs}{rows} if |
223aea40 |
533 | $self->{attrs}{rows} and $self->{attrs}{rows} < $count; |
6aeb9185 |
534 | return $count; |
89c0a5a2 |
535 | } |
536 | |
84e3c114 |
537 | sub _count { # Separated out so pager can get the full count |
538 | my $self = shift; |
539 | my $select = { count => '*' }; |
540 | my $attrs = { %{ $self->{attrs} } }; |
541 | if (my $group_by = delete $attrs->{group_by}) { |
542 | delete $attrs->{having}; |
543 | my @distinct = (ref $group_by ? @$group_by : ($group_by)); |
544 | # todo: try CONCAT for multi-column pk |
545 | my @pk = $self->result_source->primary_columns; |
546 | if (@pk == 1) { |
547 | foreach my $column (@distinct) { |
548 | if ($column =~ qr/^(?:\Q$attrs->{alias}.\E)?$pk[0]$/) { |
549 | @distinct = ($column); |
550 | last; |
551 | } |
552 | } |
553 | } |
554 | |
555 | $select = { count => { distinct => \@distinct } }; |
556 | #use Data::Dumper; die Dumper $select; |
557 | } |
558 | |
559 | $attrs->{select} = $select; |
560 | $attrs->{as} = [qw/count/]; |
561 | |
562 | # offset, order by and page are not needed to count. record_filter is cdbi |
563 | delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/; |
564 | |
565 | my ($count) = (ref $self)->new($self->result_source, $attrs)->cursor->next; |
566 | return $count; |
567 | } |
568 | |
bfab575a |
569 | =head2 count_literal |
6009260a |
570 | |
a33df5d4 |
571 | Calls L</search_literal> with the passed arguments, then L</count>. |
6009260a |
572 | |
573 | =cut |
574 | |
575 | sub count_literal { shift->search_literal(@_)->count; } |
576 | |
bfab575a |
577 | =head2 all |
ee38fa40 |
578 | |
bfab575a |
579 | Returns all elements in the resultset. Called implictly if the resultset |
580 | is returned in list context. |
ee38fa40 |
581 | |
582 | =cut |
583 | |
89c0a5a2 |
584 | sub all { |
585 | my ($self) = @_; |
223aea40 |
586 | return @{ $self->get_cache } if @{ $self->get_cache }; |
5a5bec6c |
587 | |
588 | my @obj; |
589 | |
590 | if (keys %{$self->{collapse}}) { |
591 | # Using $self->cursor->all is really just an optimisation. |
592 | # If we're collapsing has_many prefetches it probably makes |
593 | # very little difference, and this is cleaner than hacking |
594 | # _construct_object to survive the approach |
5a5bec6c |
595 | $self->cursor->reset; |
479ed423 |
596 | my @row = $self->cursor->next; |
597 | while (@row) { |
5a5bec6c |
598 | push(@obj, $self->_construct_object(@row)); |
479ed423 |
599 | @row = (exists $self->{stashed_row} |
600 | ? @{delete $self->{stashed_row}} |
601 | : $self->cursor->next); |
5a5bec6c |
602 | } |
603 | } else { |
223aea40 |
604 | @obj = map { $self->_construct_object(@$_) } $self->cursor->all; |
64acc2bc |
605 | } |
5a5bec6c |
606 | |
223aea40 |
607 | $self->set_cache(\@obj) if $self->{attrs}{cache}; |
5a5bec6c |
608 | return @obj; |
89c0a5a2 |
609 | } |
610 | |
bfab575a |
611 | =head2 reset |
ee38fa40 |
612 | |
bfab575a |
613 | Resets the resultset's cursor, so you can iterate through the elements again. |
ee38fa40 |
614 | |
615 | =cut |
616 | |
89c0a5a2 |
617 | sub reset { |
618 | my ($self) = @_; |
64acc2bc |
619 | $self->{all_cache_position} = 0; |
73f58123 |
620 | $self->cursor->reset; |
89c0a5a2 |
621 | return $self; |
622 | } |
623 | |
bfab575a |
624 | =head2 first |
ee38fa40 |
625 | |
bfab575a |
626 | Resets the resultset and returns the first element. |
ee38fa40 |
627 | |
628 | =cut |
629 | |
89c0a5a2 |
630 | sub first { |
631 | return $_[0]->reset->next; |
632 | } |
633 | |
87c4e602 |
634 | =head2 update |
635 | |
636 | =head3 Arguments: (\%values) |
c01ab172 |
637 | |
a33df5d4 |
638 | Sets the specified columns in the resultset to the supplied values. |
c01ab172 |
639 | |
640 | =cut |
641 | |
642 | sub update { |
643 | my ($self, $values) = @_; |
aa1088bf |
644 | $self->throw_exception("Values for update must be a hash") |
645 | unless ref $values eq 'HASH'; |
701da8c4 |
646 | return $self->result_source->storage->update( |
647 | $self->result_source->from, $values, $self->{cond}); |
c01ab172 |
648 | } |
649 | |
87c4e602 |
650 | =head2 update_all |
651 | |
652 | =head3 Arguments: (\%values) |
c01ab172 |
653 | |
a33df5d4 |
654 | Fetches all objects and updates them one at a time. Note that C<update_all> |
655 | will run cascade triggers while L</update> will not. |
c01ab172 |
656 | |
657 | =cut |
658 | |
659 | sub update_all { |
660 | my ($self, $values) = @_; |
aa1088bf |
661 | $self->throw_exception("Values for update must be a hash") |
662 | unless ref $values eq 'HASH'; |
c01ab172 |
663 | foreach my $obj ($self->all) { |
664 | $obj->set_columns($values)->update; |
665 | } |
666 | return 1; |
667 | } |
668 | |
bfab575a |
669 | =head2 delete |
ee38fa40 |
670 | |
c01ab172 |
671 | Deletes the contents of the resultset from its result source. |
ee38fa40 |
672 | |
673 | =cut |
674 | |
28927b50 |
675 | sub delete { |
89c0a5a2 |
676 | my ($self) = @_; |
ca4b5ab7 |
677 | my $del = {}; |
7ed3d6dc |
678 | |
679 | if (!ref($self->{cond})) { |
680 | |
681 | # No-op. No condition, we're deleting everything |
682 | |
683 | } elsif (ref $self->{cond} eq 'ARRAY') { |
684 | |
ca4b5ab7 |
685 | $del = [ map { my %hash; |
686 | foreach my $key (keys %{$_}) { |
223aea40 |
687 | $key =~ /([^.]+)$/; |
ca4b5ab7 |
688 | $hash{$1} = $_->{$key}; |
689 | }; \%hash; } @{$self->{cond}} ]; |
7ed3d6dc |
690 | |
691 | } elsif (ref $self->{cond} eq 'HASH') { |
692 | |
693 | if ((keys %{$self->{cond}})[0] eq '-and') { |
694 | |
695 | $del->{-and} = [ map { my %hash; |
696 | foreach my $key (keys %{$_}) { |
697 | $key =~ /([^.]+)$/; |
698 | $hash{$1} = $_->{$key}; |
699 | }; \%hash; } @{$self->{cond}{-and}} ]; |
700 | |
701 | } else { |
702 | |
703 | foreach my $key (keys %{$self->{cond}}) { |
223aea40 |
704 | $key =~ /([^.]+)$/; |
7ed3d6dc |
705 | $del->{$1} = $self->{cond}{$key}; |
706 | } |
ca4b5ab7 |
707 | } |
7ed3d6dc |
708 | } else { |
709 | $self->throw_exception( |
710 | "Can't delete on resultset with condition unless hash or array"); |
ca4b5ab7 |
711 | } |
7ed3d6dc |
712 | |
ca4b5ab7 |
713 | $self->result_source->storage->delete($self->result_source->from, $del); |
89c0a5a2 |
714 | return 1; |
715 | } |
716 | |
c01ab172 |
717 | =head2 delete_all |
718 | |
a33df5d4 |
719 | Fetches all objects and deletes them one at a time. Note that C<delete_all> |
720 | will run cascade triggers while L</delete> will not. |
c01ab172 |
721 | |
722 | =cut |
723 | |
724 | sub delete_all { |
725 | my ($self) = @_; |
726 | $_->delete for $self->all; |
727 | return 1; |
728 | } |
28927b50 |
729 | |
bfab575a |
730 | =head2 pager |
ee38fa40 |
731 | |
732 | Returns a L<Data::Page> object for the current resultset. Only makes |
a33df5d4 |
733 | sense for queries with a C<page> attribute. |
ee38fa40 |
734 | |
735 | =cut |
736 | |
3c5b25c5 |
737 | sub pager { |
738 | my ($self) = @_; |
739 | my $attrs = $self->{attrs}; |
aa1088bf |
740 | $self->throw_exception("Can't create pager for non-paged rs") |
741 | unless $self->{page}; |
6aeb9185 |
742 | $attrs->{rows} ||= 10; |
6aeb9185 |
743 | return $self->{pager} ||= Data::Page->new( |
84e3c114 |
744 | $self->_count, $attrs->{rows}, $self->{page}); |
3c5b25c5 |
745 | } |
746 | |
87c4e602 |
747 | =head2 page |
748 | |
749 | =head3 Arguments: ($page_num) |
ee38fa40 |
750 | |
bfab575a |
751 | Returns a new resultset for the specified page. |
ee38fa40 |
752 | |
753 | =cut |
754 | |
3c5b25c5 |
755 | sub page { |
756 | my ($self, $page) = @_; |
6aeb9185 |
757 | my $attrs = { %{$self->{attrs}} }; |
3c5b25c5 |
758 | $attrs->{page} = $page; |
701da8c4 |
759 | return (ref $self)->new($self->result_source, $attrs); |
fea3d045 |
760 | } |
761 | |
87c4e602 |
762 | =head2 new_result |
763 | |
764 | =head3 Arguments: (\%vals) |
fea3d045 |
765 | |
87f0da6a |
766 | Creates a result in the resultset's result class. |
fea3d045 |
767 | |
768 | =cut |
769 | |
770 | sub new_result { |
771 | my ($self, $values) = @_; |
701da8c4 |
772 | $self->throw_exception( "new_result needs a hash" ) |
fea3d045 |
773 | unless (ref $values eq 'HASH'); |
aa1088bf |
774 | $self->throw_exception( |
775 | "Can't abstract implicit construct, condition not a hash" |
776 | ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH')); |
fea3d045 |
777 | my %new = %$values; |
778 | my $alias = $self->{attrs}{alias}; |
779 | foreach my $key (keys %{$self->{cond}||{}}) { |
223aea40 |
780 | $new{$1} = $self->{cond}{$key} if ($key =~ m/^(?:\Q${alias}.\E)?([^.]+)$/); |
fea3d045 |
781 | } |
a50bcd52 |
782 | my $obj = $self->result_class->new(\%new); |
701da8c4 |
783 | $obj->result_source($self->result_source) if $obj->can('result_source'); |
223aea40 |
784 | return $obj; |
fea3d045 |
785 | } |
786 | |
87c4e602 |
787 | =head2 create |
788 | |
789 | =head3 Arguments: (\%vals) |
fea3d045 |
790 | |
87f0da6a |
791 | Inserts a record into the resultset and returns the object. |
fea3d045 |
792 | |
a33df5d4 |
793 | Effectively a shortcut for C<< ->new_result(\%vals)->insert >>. |
fea3d045 |
794 | |
795 | =cut |
796 | |
797 | sub create { |
798 | my ($self, $attrs) = @_; |
aa1088bf |
799 | $self->throw_exception( "create needs a hashref" ) |
800 | unless ref $attrs eq 'HASH'; |
fea3d045 |
801 | return $self->new_result($attrs)->insert; |
3c5b25c5 |
802 | } |
803 | |
87c4e602 |
804 | =head2 find_or_create |
805 | |
806 | =head3 Arguments: (\%vals, \%attrs?) |
87f0da6a |
807 | |
808 | $class->find_or_create({ key => $val, ... }); |
c2b15ecc |
809 | |
fd9f5466 |
810 | Searches for a record matching the search condition; if it doesn't find one, |
811 | creates one and returns that instead. |
87f0da6a |
812 | |
87f0da6a |
813 | my $cd = $schema->resultset('CD')->find_or_create({ |
814 | cdid => 5, |
815 | artist => 'Massive Attack', |
816 | title => 'Mezzanine', |
817 | year => 2005, |
818 | }); |
819 | |
820 | Also takes an optional C<key> attribute, to search by a specific key or unique |
821 | constraint. For example: |
822 | |
823 | my $cd = $schema->resultset('CD')->find_or_create( |
824 | { |
825 | artist => 'Massive Attack', |
826 | title => 'Mezzanine', |
827 | }, |
828 | { key => 'artist_title' } |
829 | ); |
830 | |
831 | See also L</find> and L</update_or_create>. |
832 | |
c2b15ecc |
833 | =cut |
834 | |
835 | sub find_or_create { |
836 | my $self = shift; |
87f0da6a |
837 | my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {}); |
223aea40 |
838 | my $hash = ref $_[0] eq 'HASH' ? shift : {@_}; |
87f0da6a |
839 | my $exists = $self->find($hash, $attrs); |
223aea40 |
840 | return defined $exists ? $exists : $self->create($hash); |
c2b15ecc |
841 | } |
842 | |
87f0da6a |
843 | =head2 update_or_create |
844 | |
845 | $class->update_or_create({ key => $val, ... }); |
846 | |
847 | First, search for an existing row matching one of the unique constraints |
848 | (including the primary key) on the source of this resultset. If a row is |
849 | found, update it with the other given column values. Otherwise, create a new |
850 | row. |
851 | |
852 | Takes an optional C<key> attribute to search on a specific unique constraint. |
853 | For example: |
854 | |
855 | # In your application |
856 | my $cd = $schema->resultset('CD')->update_or_create( |
857 | { |
858 | artist => 'Massive Attack', |
859 | title => 'Mezzanine', |
860 | year => 1998, |
861 | }, |
862 | { key => 'artist_title' } |
863 | ); |
864 | |
865 | If no C<key> is specified, it searches on all unique constraints defined on the |
866 | source, including the primary key. |
867 | |
868 | If the C<key> is specified as C<primary>, search only on the primary key. |
869 | |
a33df5d4 |
870 | See also L</find> and L</find_or_create>. |
871 | |
87f0da6a |
872 | =cut |
873 | |
874 | sub update_or_create { |
875 | my $self = shift; |
87f0da6a |
876 | my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {}); |
223aea40 |
877 | my $hash = ref $_[0] eq 'HASH' ? shift : {@_}; |
87f0da6a |
878 | |
701da8c4 |
879 | my %unique_constraints = $self->result_source->unique_constraints; |
87f0da6a |
880 | my @constraint_names = (exists $attrs->{key} |
881 | ? ($attrs->{key}) |
882 | : keys %unique_constraints); |
883 | |
884 | my @unique_hashes; |
885 | foreach my $name (@constraint_names) { |
886 | my @unique_cols = @{ $unique_constraints{$name} }; |
887 | my %unique_hash = |
888 | map { $_ => $hash->{$_} } |
889 | grep { exists $hash->{$_} } |
890 | @unique_cols; |
891 | |
892 | push @unique_hashes, \%unique_hash |
893 | if (scalar keys %unique_hash == scalar @unique_cols); |
894 | } |
895 | |
87f0da6a |
896 | if (@unique_hashes) { |
223aea40 |
897 | my $row = $self->single(\@unique_hashes); |
898 | if (defined $row) { |
87f0da6a |
899 | $row->set_columns($hash); |
900 | $row->update; |
223aea40 |
901 | return $row; |
87f0da6a |
902 | } |
903 | } |
904 | |
223aea40 |
905 | return $self->create($hash); |
87f0da6a |
906 | } |
907 | |
64acc2bc |
908 | =head2 get_cache |
909 | |
910 | Gets the contents of the cache for the resultset. |
911 | |
912 | =cut |
913 | |
914 | sub get_cache { |
223aea40 |
915 | shift->{all_cache} || []; |
64acc2bc |
916 | } |
917 | |
918 | =head2 set_cache |
919 | |
aa1088bf |
920 | Sets the contents of the cache for the resultset. Expects an arrayref |
921 | of objects of the same class as those produced by the resultset. |
64acc2bc |
922 | |
923 | =cut |
924 | |
925 | sub set_cache { |
926 | my ( $self, $data ) = @_; |
927 | $self->throw_exception("set_cache requires an arrayref") |
928 | if ref $data ne 'ARRAY'; |
a50bcd52 |
929 | my $result_class = $self->result_class; |
64acc2bc |
930 | foreach( @$data ) { |
aa1088bf |
931 | $self->throw_exception( |
932 | "cannot cache object of type '$_', expected '$result_class'" |
933 | ) if ref $_ ne $result_class; |
64acc2bc |
934 | } |
935 | $self->{all_cache} = $data; |
936 | } |
937 | |
938 | =head2 clear_cache |
939 | |
940 | Clears the cache for the resultset. |
941 | |
942 | =cut |
943 | |
944 | sub clear_cache { |
223aea40 |
945 | shift->set_cache([]); |
64acc2bc |
946 | } |
947 | |
948 | =head2 related_resultset |
949 | |
950 | Returns a related resultset for the supplied relationship name. |
951 | |
24d67825 |
952 | $artist_rs = $schema->resultset('CD')->related_resultset('Artist'); |
64acc2bc |
953 | |
954 | =cut |
955 | |
956 | sub related_resultset { |
957 | my ( $self, $rel, @rest ) = @_; |
958 | $self->{related_resultsets} ||= {}; |
223aea40 |
959 | return $self->{related_resultsets}{$rel} ||= do { |
960 | #warn "fetching related resultset for rel '$rel'"; |
961 | my $rel_obj = $self->result_source->relationship_info($rel); |
962 | $self->throw_exception( |
963 | "search_related: result source '" . $self->result_source->name . |
964 | "' has no such relationship ${rel}") |
965 | unless $rel_obj; #die Dumper $self->{attrs}; |
966 | |
967 | my $rs = $self->search(undef, { join => $rel }); |
968 | my $alias = defined $rs->{attrs}{seen_join}{$rel} |
969 | && $rs->{attrs}{seen_join}{$rel} > 1 |
970 | ? join('_', $rel, $rs->{attrs}{seen_join}{$rel}) |
971 | : $rel; |
972 | |
64acc2bc |
973 | $self->result_source->schema->resultset($rel_obj->{class} |
974 | )->search( undef, |
975 | { %{$rs->{attrs}}, |
976 | alias => $alias, |
223aea40 |
977 | select => undef, |
978 | as => undef } |
979 | )->search(@rest); |
980 | }; |
64acc2bc |
981 | } |
982 | |
701da8c4 |
983 | =head2 throw_exception |
984 | |
985 | See Schema's throw_exception |
986 | |
987 | =cut |
988 | |
989 | sub throw_exception { |
990 | my $self=shift; |
991 | $self->result_source->schema->throw_exception(@_); |
992 | } |
993 | |
40dbc108 |
994 | =head1 ATTRIBUTES |
076652e8 |
995 | |
a33df5d4 |
996 | The resultset takes various attributes that modify its behavior. Here's an |
997 | overview of them: |
bfab575a |
998 | |
999 | =head2 order_by |
076652e8 |
1000 | |
24d67825 |
1001 | Which column(s) to order the results by. This is currently passed |
1002 | through directly to SQL, so you can give e.g. C<year DESC> for a |
1003 | descending order on the column `year'. |
076652e8 |
1004 | |
5e8b1b2a |
1005 | =head2 columns |
87c4e602 |
1006 | |
1007 | =head3 Arguments: (arrayref) |
976f3686 |
1008 | |
a33df5d4 |
1009 | Shortcut to request a particular set of columns to be retrieved. Adds |
1010 | C<me.> onto the start of any column without a C<.> in it and sets C<select> |
5e8b1b2a |
1011 | from that, then auto-populates C<as> from C<select> as normal. (You may also |
1012 | use the C<cols> attribute, as in earlier versions of DBIC.) |
976f3686 |
1013 | |
87c4e602 |
1014 | =head2 include_columns |
1015 | |
1016 | =head3 Arguments: (arrayref) |
5ac6a044 |
1017 | |
1018 | Shortcut to include additional columns in the returned results - for example |
1019 | |
24d67825 |
1020 | $schema->resultset('CD')->search(undef, { |
1021 | include_columns => ['artist.name'], |
1022 | join => ['artist'] |
1023 | }); |
5ac6a044 |
1024 | |
24d67825 |
1025 | would return all CDs and include a 'name' column to the information |
1026 | passed to object inflation |
5ac6a044 |
1027 | |
87c4e602 |
1028 | =head2 select |
1029 | |
1030 | =head3 Arguments: (arrayref) |
976f3686 |
1031 | |
4a28c340 |
1032 | Indicates which columns should be selected from the storage. You can use |
1033 | column names, or in the case of RDBMS back ends, function or stored procedure |
1034 | names: |
1035 | |
24d67825 |
1036 | $rs = $schema->resultset('Employee')->search(undef, { |
1037 | select => [ |
1038 | 'name', |
1039 | { count => 'employeeid' }, |
1040 | { sum => 'salary' } |
1041 | ] |
1042 | }); |
4a28c340 |
1043 | |
1044 | When you use function/stored procedure names and do not supply an C<as> |
1045 | attribute, the column names returned are storage-dependent. E.g. MySQL would |
24d67825 |
1046 | return a column named C<count(employeeid)> in the above example. |
976f3686 |
1047 | |
87c4e602 |
1048 | =head2 as |
1049 | |
1050 | =head3 Arguments: (arrayref) |
076652e8 |
1051 | |
4a28c340 |
1052 | Indicates column names for object inflation. This is used in conjunction with |
1053 | C<select>, usually when C<select> contains one or more function or stored |
1054 | procedure names: |
1055 | |
24d67825 |
1056 | $rs = $schema->resultset('Employee')->search(undef, { |
1057 | select => [ |
1058 | 'name', |
1059 | { count => 'employeeid' } |
1060 | ], |
a0638a7b |
1061 | as => ['name', 'employee_count'], |
24d67825 |
1062 | }); |
4a28c340 |
1063 | |
24d67825 |
1064 | my $employee = $rs->first(); # get the first Employee |
4a28c340 |
1065 | |
1066 | If the object against which the search is performed already has an accessor |
1067 | matching a column name specified in C<as>, the value can be retrieved using |
1068 | the accessor as normal: |
1069 | |
24d67825 |
1070 | my $name = $employee->name(); |
4a28c340 |
1071 | |
1072 | If on the other hand an accessor does not exist in the object, you need to |
1073 | use C<get_column> instead: |
1074 | |
24d67825 |
1075 | my $employee_count = $employee->get_column('employee_count'); |
4a28c340 |
1076 | |
1077 | You can create your own accessors if required - see |
1078 | L<DBIx::Class::Manual::Cookbook> for details. |
ee38fa40 |
1079 | |
bfab575a |
1080 | =head2 join |
ee38fa40 |
1081 | |
a33df5d4 |
1082 | Contains a list of relationships that should be joined for this query. For |
1083 | example: |
1084 | |
1085 | # Get CDs by Nine Inch Nails |
1086 | my $rs = $schema->resultset('CD')->search( |
1087 | { 'artist.name' => 'Nine Inch Nails' }, |
1088 | { join => 'artist' } |
1089 | ); |
1090 | |
1091 | Can also contain a hash reference to refer to the other relation's relations. |
1092 | For example: |
1093 | |
1094 | package MyApp::Schema::Track; |
1095 | use base qw/DBIx::Class/; |
1096 | __PACKAGE__->table('track'); |
1097 | __PACKAGE__->add_columns(qw/trackid cd position title/); |
1098 | __PACKAGE__->set_primary_key('trackid'); |
1099 | __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD'); |
1100 | 1; |
1101 | |
1102 | # In your application |
1103 | my $rs = $schema->resultset('Artist')->search( |
1104 | { 'track.title' => 'Teardrop' }, |
1105 | { |
1106 | join => { cd => 'track' }, |
1107 | order_by => 'artist.name', |
1108 | } |
1109 | ); |
1110 | |
2cb360cc |
1111 | If the same join is supplied twice, it will be aliased to <rel>_2 (and |
1112 | similarly for a third time). For e.g. |
1113 | |
24d67825 |
1114 | my $rs = $schema->resultset('Artist')->search({ |
1115 | 'cds.title' => 'Down to Earth', |
1116 | 'cds_2.title' => 'Popular', |
1117 | }, { |
1118 | join => [ qw/cds cds/ ], |
1119 | }); |
2cb360cc |
1120 | |
24d67825 |
1121 | will return a set of all artists that have both a cd with title 'Down |
1122 | to Earth' and a cd with title 'Popular'. |
2cb360cc |
1123 | |
1124 | If you want to fetch related objects from other tables as well, see C<prefetch> |
ae1c90a1 |
1125 | below. |
ee38fa40 |
1126 | |
87c4e602 |
1127 | =head2 prefetch |
1128 | |
1129 | =head3 Arguments: arrayref/hashref |
ee38fa40 |
1130 | |
ae1c90a1 |
1131 | Contains one or more relationships that should be fetched along with the main |
bfab575a |
1132 | query (when they are accessed afterwards they will have already been |
a33df5d4 |
1133 | "prefetched"). This is useful for when you know you will need the related |
ae1c90a1 |
1134 | objects, because it saves at least one query: |
1135 | |
1136 | my $rs = $schema->resultset('Tag')->search( |
5e8b1b2a |
1137 | undef, |
ae1c90a1 |
1138 | { |
1139 | prefetch => { |
1140 | cd => 'artist' |
1141 | } |
1142 | } |
1143 | ); |
1144 | |
1145 | The initial search results in SQL like the following: |
1146 | |
1147 | SELECT tag.*, cd.*, artist.* FROM tag |
1148 | JOIN cd ON tag.cd = cd.cdid |
1149 | JOIN artist ON cd.artist = artist.artistid |
1150 | |
1151 | L<DBIx::Class> has no need to go back to the database when we access the |
1152 | C<cd> or C<artist> relationships, which saves us two SQL statements in this |
1153 | case. |
1154 | |
2cb360cc |
1155 | Simple prefetches will be joined automatically, so there is no need |
1156 | for a C<join> attribute in the above search. If you're prefetching to |
1157 | depth (e.g. { cd => { artist => 'label' } or similar), you'll need to |
1158 | specify the join as well. |
ae1c90a1 |
1159 | |
1160 | C<prefetch> can be used with the following relationship types: C<belongs_to>, |
2cb360cc |
1161 | C<has_one> (or if you're using C<add_relationship>, any relationship declared |
1162 | with an accessor type of 'single' or 'filter'). |
ee38fa40 |
1163 | |
87c4e602 |
1164 | =head2 from |
1165 | |
1166 | =head3 Arguments: (arrayref) |
ee38fa40 |
1167 | |
4a28c340 |
1168 | The C<from> attribute gives you manual control over the C<FROM> clause of SQL |
1169 | statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN> |
1170 | clauses. |
ee38fa40 |
1171 | |
a33df5d4 |
1172 | NOTE: Use this on your own risk. This allows you to shoot off your foot! |
4a28c340 |
1173 | C<join> will usually do what you need and it is strongly recommended that you |
1174 | avoid using C<from> unless you cannot achieve the desired result using C<join>. |
1175 | |
1176 | In simple terms, C<from> works as follows: |
1177 | |
1178 | [ |
1179 | { <alias> => <table>, -join-type => 'inner|left|right' } |
1180 | [] # nested JOIN (optional) |
1181 | { <table.column> = <foreign_table.foreign_key> } |
1182 | ] |
1183 | |
1184 | JOIN |
1185 | <alias> <table> |
1186 | [JOIN ...] |
1187 | ON <table.column> = <foreign_table.foreign_key> |
1188 | |
1189 | An easy way to follow the examples below is to remember the following: |
1190 | |
1191 | Anything inside "[]" is a JOIN |
1192 | Anything inside "{}" is a condition for the enclosing JOIN |
1193 | |
1194 | The following examples utilize a "person" table in a family tree application. |
1195 | In order to express parent->child relationships, this table is self-joined: |
1196 | |
1197 | # Person->belongs_to('father' => 'Person'); |
1198 | # Person->belongs_to('mother' => 'Person'); |
1199 | |
1200 | C<from> can be used to nest joins. Here we return all children with a father, |
1201 | then search against all mothers of those children: |
1202 | |
1203 | $rs = $schema->resultset('Person')->search( |
5e8b1b2a |
1204 | undef, |
4a28c340 |
1205 | { |
1206 | alias => 'mother', # alias columns in accordance with "from" |
1207 | from => [ |
1208 | { mother => 'person' }, |
1209 | [ |
1210 | [ |
1211 | { child => 'person' }, |
1212 | [ |
1213 | { father => 'person' }, |
1214 | { 'father.person_id' => 'child.father_id' } |
1215 | ] |
1216 | ], |
1217 | { 'mother.person_id' => 'child.mother_id' } |
fd9f5466 |
1218 | ], |
4a28c340 |
1219 | ] |
1220 | }, |
1221 | ); |
1222 | |
1223 | # Equivalent SQL: |
1224 | # SELECT mother.* FROM person mother |
1225 | # JOIN ( |
1226 | # person child |
1227 | # JOIN person father |
1228 | # ON ( father.person_id = child.father_id ) |
1229 | # ) |
1230 | # ON ( mother.person_id = child.mother_id ) |
1231 | |
1232 | The type of any join can be controlled manually. To search against only people |
1233 | with a father in the person table, we could explicitly use C<INNER JOIN>: |
1234 | |
1235 | $rs = $schema->resultset('Person')->search( |
5e8b1b2a |
1236 | undef, |
4a28c340 |
1237 | { |
1238 | alias => 'child', # alias columns in accordance with "from" |
1239 | from => [ |
1240 | { child => 'person' }, |
1241 | [ |
1242 | { father => 'person', -join-type => 'inner' }, |
1243 | { 'father.id' => 'child.father_id' } |
1244 | ], |
1245 | ] |
1246 | }, |
1247 | ); |
1248 | |
1249 | # Equivalent SQL: |
1250 | # SELECT child.* FROM person child |
1251 | # INNER JOIN person father ON child.father_id = father.id |
ee38fa40 |
1252 | |
bfab575a |
1253 | =head2 page |
076652e8 |
1254 | |
a33df5d4 |
1255 | For a paged resultset, specifies which page to retrieve. Leave unset |
bfab575a |
1256 | for an unpaged resultset. |
076652e8 |
1257 | |
bfab575a |
1258 | =head2 rows |
076652e8 |
1259 | |
4a28c340 |
1260 | For a paged resultset, how many rows per page: |
1261 | |
1262 | rows => 10 |
1263 | |
1264 | Can also be used to simulate an SQL C<LIMIT>. |
076652e8 |
1265 | |
87c4e602 |
1266 | =head2 group_by |
1267 | |
1268 | =head3 Arguments: (arrayref) |
54540863 |
1269 | |
bda4c2b8 |
1270 | A arrayref of columns to group by. Can include columns of joined tables. |
54540863 |
1271 | |
675ce4a6 |
1272 | group_by => [qw/ column1 column2 ... /] |
1273 | |
54540863 |
1274 | =head2 distinct |
1275 | |
a33df5d4 |
1276 | Set to 1 to group by all columns. |
1277 | |
534ca143 |
1278 | =head2 cache |
1279 | |
1280 | Set to 1 to cache search results. This prevents extra SQL queries if you |
1281 | revisit rows in your ResultSet: |
1282 | |
1283 | my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } ); |
1284 | |
1285 | while( my $artist = $resultset->next ) { |
1286 | ... do stuff ... |
1287 | } |
1288 | |
1289 | $rs->first; # without cache, this would issue a query |
1290 | |
1291 | By default, searches are not cached. |
1292 | |
a33df5d4 |
1293 | For more examples of using these attributes, see |
1294 | L<DBIx::Class::Manual::Cookbook>. |
54540863 |
1295 | |
bfab575a |
1296 | =cut |
076652e8 |
1297 | |
89c0a5a2 |
1298 | 1; |