Commit | Line | Data |
89c0a5a2 |
1 | package DBIx::Class::ResultSet; |
2 | |
3 | use strict; |
4 | use warnings; |
5 | use overload |
6 | '0+' => 'count', |
7 | fallback => 1; |
3c5b25c5 |
8 | use Data::Page; |
89c0a5a2 |
9 | |
ee38fa40 |
10 | =head1 NAME |
11 | |
bfab575a |
12 | DBIx::Class::ResultSet - Responsible for fetching and creating resultset. |
ee38fa40 |
13 | |
bfab575a |
14 | =head1 SYNOPSIS |
ee38fa40 |
15 | |
bfab575a |
16 | my $rs = MyApp::DB::Class->search(registered => 1); |
17 | my @rows = MyApp::DB::Class->search(foo => 'bar'); |
ee38fa40 |
18 | |
19 | =head1 DESCRIPTION |
20 | |
bfab575a |
21 | The resultset is also known as an iterator. It is responsible for handling |
22 | queries that may return an arbitrary number of rows, e.g. via C<search> |
23 | or a C<has_many> relationship. |
ee38fa40 |
24 | |
25 | =head1 METHODS |
26 | |
976f3686 |
27 | =head2 new($source, \%$attrs) |
ee38fa40 |
28 | |
976f3686 |
29 | The resultset constructor. Takes a source object (usually a DBIx::Class::Table) |
30 | and an attribute hash (see below for more information on attributes). Does |
31 | not perform any queries -- these are executed as needed by the other methods. |
ee38fa40 |
32 | |
33 | =cut |
34 | |
89c0a5a2 |
35 | sub new { |
cda04c3a |
36 | my ($class, $source, $attrs) = @_; |
89c0a5a2 |
37 | #use Data::Dumper; warn Dumper(@_); |
2f5911b2 |
38 | $class = ref $class if ref $class; |
89c0a5a2 |
39 | $attrs = { %{ $attrs || {} } }; |
c7ce65e6 |
40 | my %seen; |
976f3686 |
41 | if (!$attrs->{select}) { |
42 | my @cols = ($attrs->{cols} |
43 | ? @{delete $attrs->{cols}} |
44 | : $source->result_class->_select_columns); |
45 | $attrs->{select} = [ map { m/\./ ? $_ : "me.$_" } @cols ]; |
46 | } |
47 | $attrs->{as} ||= [ map { m/^me\.(.*)$/ ? $1 : $_ } @{$attrs->{select}} ]; |
48 | #use Data::Dumper; warn Dumper(@{$attrs}{qw/select as/}); |
cda04c3a |
49 | $attrs->{from} ||= [ { 'me' => $source->name } ]; |
fef5d100 |
50 | if ($attrs->{join}) { |
c7ce65e6 |
51 | foreach my $j (ref $attrs->{join} eq 'ARRAY' |
52 | ? (@{$attrs->{join}}) : ($attrs->{join})) { |
53 | if (ref $j eq 'HASH') { |
54 | $seen{$_} = 1 foreach keys %$j; |
55 | } else { |
56 | $seen{$j} = 1; |
57 | } |
58 | } |
cda04c3a |
59 | push(@{$attrs->{from}}, $source->result_class->_resolve_join($attrs->{join}, 'me')); |
c7ce65e6 |
60 | } |
54540863 |
61 | $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct}; |
c7ce65e6 |
62 | foreach my $pre (@{$attrs->{prefetch} || []}) { |
cda04c3a |
63 | push(@{$attrs->{from}}, $source->result_class->_resolve_join($pre, 'me')) |
c7ce65e6 |
64 | unless $seen{$pre}; |
976f3686 |
65 | my @pre = |
c7ce65e6 |
66 | map { "$pre.$_" } |
976f3686 |
67 | $source->result_class->_relationships->{$pre}->{class}->columns; |
68 | push(@{$attrs->{select}}, @pre); |
69 | push(@{$attrs->{as}}, @pre); |
fef5d100 |
70 | } |
89c0a5a2 |
71 | my $new = { |
cda04c3a |
72 | source => $source, |
89c0a5a2 |
73 | cond => $attrs->{where}, |
0a3c5b43 |
74 | from => $attrs->{from}, |
3c5b25c5 |
75 | count => undef, |
76 | pager => undef, |
89c0a5a2 |
77 | attrs => $attrs }; |
2f5911b2 |
78 | bless ($new, $class); |
976f3686 |
79 | $new->pager if $attrs->{page}; |
9229f20a |
80 | return $new; |
89c0a5a2 |
81 | } |
82 | |
bfab575a |
83 | =head2 search |
0a3c5b43 |
84 | |
6009260a |
85 | my @obj = $rs->search({ foo => 3 }); # "... WHERE foo = 3" |
86 | my $new_rs = $rs->search({ foo => 3 }); |
87 | |
88 | If you need to pass in additional attributes but no additional condition, |
89 | call it as ->search(undef, \%attrs); |
90 | |
91 | my @all = $class->search({}, { cols => [qw/foo bar/] }); # "SELECT foo, bar FROM $class_table" |
0a3c5b43 |
92 | |
93 | =cut |
94 | |
95 | sub search { |
96 | my $self = shift; |
97 | |
6009260a |
98 | #use Data::Dumper;warn Dumper(@_); |
99 | |
0a3c5b43 |
100 | my $attrs = { %{$self->{attrs}} }; |
101 | if (@_ > 1 && ref $_[$#_] eq 'HASH') { |
102 | $attrs = { %{ pop(@_) } }; |
103 | } |
104 | |
6009260a |
105 | my $where = ((@_ == 1 || ref $_[0] eq "HASH") ? shift : {@_}); |
0a3c5b43 |
106 | if (defined $where) { |
107 | $where = (defined $attrs->{where} |
108 | ? { '-and' => [ $where, $attrs->{where} ] } |
109 | : $where); |
110 | $attrs->{where} = $where; |
111 | } |
112 | |
113 | my $rs = $self->new($self->{source}, $attrs); |
114 | |
115 | return (wantarray ? $rs->all : $rs); |
116 | } |
117 | |
bfab575a |
118 | =head2 search_literal |
6009260a |
119 | my @obj = $rs->search_literal($literal_where_cond, @bind); |
120 | my $new_rs = $rs->search_literal($literal_where_cond, @bind); |
121 | |
122 | Pass a literal chunk of SQL to be added to the conditional part of the |
123 | resultset |
124 | |
bfab575a |
125 | =cut |
126 | |
6009260a |
127 | sub search_literal { |
128 | my ($self, $cond, @vals) = @_; |
129 | my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {}); |
130 | $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ]; |
131 | return $self->search(\$cond, $attrs); |
132 | } |
0a3c5b43 |
133 | |
bfab575a |
134 | =head2 cursor |
ee38fa40 |
135 | |
bfab575a |
136 | Returns a storage-driven cursor to the given resultset. |
ee38fa40 |
137 | |
138 | =cut |
139 | |
73f58123 |
140 | sub cursor { |
141 | my ($self) = @_; |
2f5911b2 |
142 | my ($source, $attrs) = @{$self}{qw/source attrs/}; |
3c5b25c5 |
143 | if ($attrs->{page}) { |
144 | $attrs->{rows} = $self->pager->entries_per_page; |
145 | $attrs->{offset} = $self->pager->skipped; |
146 | } |
73f58123 |
147 | return $self->{cursor} |
976f3686 |
148 | ||= $source->storage->select($self->{from}, $attrs->{select}, |
73f58123 |
149 | $attrs->{where},$attrs); |
150 | } |
151 | |
bfab575a |
152 | =head2 search_like |
58a4bd18 |
153 | |
154 | Identical to search except defaults to 'LIKE' instead of '=' in condition |
155 | |
156 | =cut |
157 | |
158 | sub search_like { |
159 | my $class = shift; |
160 | my $attrs = { }; |
161 | if (@_ > 1 && ref $_[$#_] eq 'HASH') { |
162 | $attrs = pop(@_); |
163 | } |
164 | my $query = ref $_[0] eq "HASH" ? { %{shift()} }: {@_}; |
165 | $query->{$_} = { 'like' => $query->{$_} } for keys %$query; |
166 | return $class->search($query, { %$attrs }); |
167 | } |
168 | |
bfab575a |
169 | =head2 slice($first, $last) |
ee38fa40 |
170 | |
bfab575a |
171 | Returns a subset of elements from the resultset. |
ee38fa40 |
172 | |
173 | =cut |
174 | |
89c0a5a2 |
175 | sub slice { |
176 | my ($self, $min, $max) = @_; |
177 | my $attrs = { %{ $self->{attrs} || {} } }; |
cda04c3a |
178 | $self->{source}->result_class->throw("Can't slice without where") unless $attrs->{where}; |
89c0a5a2 |
179 | $attrs->{offset} = $min; |
180 | $attrs->{rows} = ($max ? ($max - $min + 1) : 1); |
2f5911b2 |
181 | my $slice = $self->new($self->{source}, $attrs); |
89c0a5a2 |
182 | return (wantarray ? $slice->all : $slice); |
183 | } |
184 | |
bfab575a |
185 | =head2 next |
ee38fa40 |
186 | |
bfab575a |
187 | Returns the next element in the resultset (undef is there is none). |
ee38fa40 |
188 | |
189 | =cut |
190 | |
89c0a5a2 |
191 | sub next { |
192 | my ($self) = @_; |
73f58123 |
193 | my @row = $self->cursor->next; |
89c0a5a2 |
194 | return unless (@row); |
c7ce65e6 |
195 | return $self->_construct_object(@row); |
196 | } |
197 | |
198 | sub _construct_object { |
199 | my ($self, @row) = @_; |
976f3686 |
200 | my @cols = @{ $self->{attrs}{as} }; |
201 | #warn "@cols -> @row"; |
3cbddeb1 |
202 | @cols = grep { /\(/ or ! /\./ } @cols; |
33ce49d6 |
203 | my $new; |
c7ce65e6 |
204 | unless ($self->{attrs}{prefetch}) { |
cda04c3a |
205 | $new = $self->{source}->result_class->_row_to_object(\@cols, \@row); |
c7ce65e6 |
206 | } else { |
207 | my @main = splice(@row, 0, scalar @cols); |
cda04c3a |
208 | $new = $self->{source}->result_class->_row_to_object(\@cols, \@main); |
c7ce65e6 |
209 | PRE: foreach my $pre (@{$self->{attrs}{prefetch}}) { |
cda04c3a |
210 | my $rel_obj = $self->{source}->result_class->_relationships->{$pre}; |
211 | my $pre_class = $self->{source}->result_class->resolve_class($rel_obj->{class}); |
dd417d06 |
212 | my @pre_cols = $pre_class->_select_columns; |
c7ce65e6 |
213 | my @vals = splice(@row, 0, scalar @pre_cols); |
dd417d06 |
214 | my $fetched = $pre_class->_row_to_object(\@pre_cols, \@vals); |
cda04c3a |
215 | $self->{source}->result_class->throw("No accessor for prefetched $pre") |
c7ce65e6 |
216 | unless defined $rel_obj->{attrs}{accessor}; |
217 | if ($rel_obj->{attrs}{accessor} eq 'single') { |
218 | foreach my $pri ($rel_obj->{class}->primary_columns) { |
7cd300ea |
219 | unless (defined $fetched->get_column($pri)) { |
220 | undef $fetched; |
221 | last; |
222 | } |
c7ce65e6 |
223 | } |
224 | $new->{_relationship_data}{$pre} = $fetched; |
225 | } elsif ($rel_obj->{attrs}{accessor} eq 'filter') { |
226 | $new->{_inflated_column}{$pre} = $fetched; |
227 | } else { |
cda04c3a |
228 | $self->{source}->result_class->throw("Don't know how to store prefetched $pre"); |
c7ce65e6 |
229 | } |
230 | } |
c7ce65e6 |
231 | } |
33ce49d6 |
232 | $new = $self->{attrs}{record_filter}->($new) |
233 | if exists $self->{attrs}{record_filter}; |
234 | return $new; |
89c0a5a2 |
235 | } |
236 | |
bfab575a |
237 | =head2 count |
ee38fa40 |
238 | |
bfab575a |
239 | Performs an SQL C<COUNT> with the same query as the resultset was built |
6009260a |
240 | with to find the number of elements. If passed arguments, does a search |
241 | on the resultset and counts the results of that. |
ee38fa40 |
242 | |
243 | =cut |
244 | |
89c0a5a2 |
245 | sub count { |
6009260a |
246 | my $self = shift; |
247 | return $self->search(@_)->count if @_ && defined $_[0]; |
54540863 |
248 | die "Unable to ->count with a GROUP BY" if defined $self->{attrs}{group_by}; |
3c5b25c5 |
249 | unless ($self->{count}) { |
976f3686 |
250 | my $attrs = { %{ $self->{attrs} }, |
54540863 |
251 | select => { 'count' => '*' }, |
252 | as => [ 'count' ] }; |
976f3686 |
253 | # offset and order by are not needed to count, page, join and prefetch |
254 | # will get in the way (add themselves to from again ...) |
255 | delete $attrs->{$_} for qw/offset order_by page join prefetch/; |
3c5b25c5 |
256 | |
257 | my @cols = 'COUNT(*)'; |
976f3686 |
258 | ($self->{count}) = $self->search(undef, $attrs)->cursor->next; |
3c5b25c5 |
259 | } |
260 | return 0 unless $self->{count}; |
9229f20a |
261 | return $self->{pager}->entries_on_this_page if ($self->{pager}); |
976f3686 |
262 | return ( $self->{attrs}->{rows} && $self->{attrs}->{rows} < $self->{count} ) |
263 | ? $self->{attrs}->{rows} |
3c5b25c5 |
264 | : $self->{count}; |
89c0a5a2 |
265 | } |
266 | |
bfab575a |
267 | =head2 count_literal |
6009260a |
268 | |
bfab575a |
269 | Calls search_literal with the passed arguments, then count. |
6009260a |
270 | |
271 | =cut |
272 | |
273 | sub count_literal { shift->search_literal(@_)->count; } |
274 | |
bfab575a |
275 | =head2 all |
ee38fa40 |
276 | |
bfab575a |
277 | Returns all elements in the resultset. Called implictly if the resultset |
278 | is returned in list context. |
ee38fa40 |
279 | |
280 | =cut |
281 | |
89c0a5a2 |
282 | sub all { |
283 | my ($self) = @_; |
c7ce65e6 |
284 | return map { $self->_construct_object(@$_); } |
73f58123 |
285 | $self->cursor->all; |
89c0a5a2 |
286 | } |
287 | |
bfab575a |
288 | =head2 reset |
ee38fa40 |
289 | |
bfab575a |
290 | Resets the resultset's cursor, so you can iterate through the elements again. |
ee38fa40 |
291 | |
292 | =cut |
293 | |
89c0a5a2 |
294 | sub reset { |
295 | my ($self) = @_; |
73f58123 |
296 | $self->cursor->reset; |
89c0a5a2 |
297 | return $self; |
298 | } |
299 | |
bfab575a |
300 | =head2 first |
ee38fa40 |
301 | |
bfab575a |
302 | Resets the resultset and returns the first element. |
ee38fa40 |
303 | |
304 | =cut |
305 | |
89c0a5a2 |
306 | sub first { |
307 | return $_[0]->reset->next; |
308 | } |
309 | |
bfab575a |
310 | =head2 delete |
ee38fa40 |
311 | |
38659261 |
312 | Deletes all elements in the resultset. |
ee38fa40 |
313 | |
314 | =cut |
315 | |
28927b50 |
316 | sub delete { |
89c0a5a2 |
317 | my ($self) = @_; |
318 | $_->delete for $self->all; |
319 | return 1; |
320 | } |
321 | |
28927b50 |
322 | *delete_all = \&delete; # Yeah, yeah, yeah ... |
323 | |
bfab575a |
324 | =head2 pager |
ee38fa40 |
325 | |
326 | Returns a L<Data::Page> object for the current resultset. Only makes |
327 | sense for queries with page turned on. |
328 | |
329 | =cut |
330 | |
3c5b25c5 |
331 | sub pager { |
332 | my ($self) = @_; |
333 | my $attrs = $self->{attrs}; |
334 | delete $attrs->{offset}; |
335 | my $rows_per_page = delete $attrs->{rows} || 10; |
336 | $self->{pager} ||= Data::Page->new( |
337 | $self->count, $rows_per_page, $attrs->{page} || 1); |
338 | $attrs->{rows} = $rows_per_page; |
339 | return $self->{pager}; |
340 | } |
341 | |
bfab575a |
342 | =head2 page($page_num) |
ee38fa40 |
343 | |
bfab575a |
344 | Returns a new resultset for the specified page. |
ee38fa40 |
345 | |
346 | =cut |
347 | |
3c5b25c5 |
348 | sub page { |
349 | my ($self, $page) = @_; |
350 | my $attrs = $self->{attrs}; |
351 | $attrs->{page} = $page; |
2f5911b2 |
352 | return $self->new($self->{source}, $attrs); |
3c5b25c5 |
353 | } |
354 | |
076652e8 |
355 | =head1 Attributes |
356 | |
bfab575a |
357 | The resultset takes various attributes that modify its behavior. |
358 | Here's an overview of them: |
359 | |
360 | =head2 order_by |
076652e8 |
361 | |
bfab575a |
362 | Which column(s) to order the results by. This is currently passed |
363 | through directly to SQL, so you can give e.g. C<foo DESC> for a |
364 | descending order. |
076652e8 |
365 | |
976f3686 |
366 | =head2 cols (arrayref) |
367 | |
368 | Shortcut to request a particular set of columns to be retrieved - adds |
369 | 'me.' onto the start of any column without a '.' in it and sets 'select' |
370 | from that, then auto-populates 'as' from 'select' as normal |
371 | |
372 | =head2 select (arrayref) |
373 | |
374 | Indicates which columns should be selected from the storage |
375 | |
376 | =head2 as (arrayref) |
076652e8 |
377 | |
976f3686 |
378 | Indicates column names for object inflation |
ee38fa40 |
379 | |
bfab575a |
380 | =head2 join |
ee38fa40 |
381 | |
bfab575a |
382 | Contains a list of relationships that should be joined for this query. Can also |
383 | contain a hash reference to refer to that relation's relations. So, if one column |
384 | in your class C<belongs_to> foo and another C<belongs_to> bar, you can do |
385 | C<< join => [qw/ foo bar /] >> to join both (and e.g. use them for C<order_by>). |
386 | If a foo contains many margles and you want to join those too, you can do |
387 | C<< join => { foo => 'margle' } >>. If you want to fetch the columns from the |
388 | related table as well, see C<prefetch> below. |
ee38fa40 |
389 | |
bfab575a |
390 | =head2 prefetch |
ee38fa40 |
391 | |
bfab575a |
392 | Contains a list of relationships that should be fetched along with the main |
393 | query (when they are accessed afterwards they will have already been |
394 | "prefetched"). This is useful for when you know you will need the related |
395 | object(s), because it saves a query. Currently limited to prefetching |
396 | one relationship deep, so unlike C<join>, prefetch must be an arrayref. |
ee38fa40 |
397 | |
bfab575a |
398 | =head2 from |
ee38fa40 |
399 | |
bfab575a |
400 | This attribute can contain a arrayref of elements. Each element can be another |
ee38fa40 |
401 | arrayref, to nest joins, or it can be a hash which represents the two sides |
402 | of the join. |
403 | |
bfab575a |
404 | NOTE: Use this on your own risk. This allows you to shoot your foot off! |
ee38fa40 |
405 | |
bfab575a |
406 | =head2 page |
076652e8 |
407 | |
bfab575a |
408 | For a paged resultset, specifies which page to retrieve. Leave unset |
409 | for an unpaged resultset. |
076652e8 |
410 | |
bfab575a |
411 | =head2 rows |
076652e8 |
412 | |
bfab575a |
413 | For a paged resultset, how many rows per page |
076652e8 |
414 | |
54540863 |
415 | =head2 group_by |
416 | |
417 | A list of columns to group by (note that 'count' doesn't work on grouped |
418 | resultsets) |
419 | |
420 | =head2 distinct |
421 | |
422 | Set to 1 to group by all columns |
423 | |
bfab575a |
424 | =cut |
076652e8 |
425 | |
89c0a5a2 |
426 | 1; |