use strict;
use warnings;
use overload
- '0+' => 'count',
+ '0+' => \&count,
+ 'bool' => sub { 1; },
fallback => 1;
use Data::Page;
+use Storable;
+use Scalar::Util qw/weaken/;
+
+use base qw/DBIx::Class/;
+__PACKAGE__->load_components(qw/AccessorGroup/);
+__PACKAGE__->mk_group_accessors('simple' => qw/result_source result_class/);
=head1 NAME
=head1 SYNOPSIS
-my $rs = MyApp::DB::Class->search(registered => 1);
-my @rows = MyApp::DB::Class->search(foo => 'bar');
+ my $rs = $schema->resultset('User')->search(registered => 1);
+ my @rows = $schema->resultset('CD')->search(year => 2005);
=head1 DESCRIPTION
The resultset is also known as an iterator. It is responsible for handling
-queries that may return an arbitrary number of rows, e.g. via C<search>
+queries that may return an arbitrary number of rows, e.g. via L</search>
or a C<has_many> relationship.
+In the examples below, the following table classes are used:
+
+ package MyApp::Schema::Artist;
+ use base qw/DBIx::Class/;
+ __PACKAGE__->load_components(qw/Core/);
+ __PACKAGE__->table('artist');
+ __PACKAGE__->add_columns(qw/artistid name/);
+ __PACKAGE__->set_primary_key('artistid');
+ __PACKAGE__->has_many(cds => 'MyApp::Schema::CD');
+ 1;
+
+ package MyApp::Schema::CD;
+ use base qw/DBIx::Class/;
+ __PACKAGE__->load_components(qw/Core/);
+ __PACKAGE__->table('cd');
+ __PACKAGE__->add_columns(qw/cdid artist title year/);
+ __PACKAGE__->set_primary_key('cdid');
+ __PACKAGE__->belongs_to(artist => 'MyApp::Schema::Artist');
+ 1;
+
=head1 METHODS
-=head2 new($source, \%$attrs)
+=head2 new
+
+=over 4
+
+=item Arguments: ($source, \%$attrs)
+
+=back
-The resultset constructor. Takes a source object (usually a DBIx::Class::Table)
-and an attribute hash (see below for more information on attributes). Does
-not perform any queries -- these are executed as needed by the other methods.
+The resultset constructor. Takes a source object (usually a
+L<DBIx::Class::ResultSourceProxy::Table>) and an attribute hash (see
+L</ATTRIBUTES> below). Does not perform any queries -- these are
+executed as needed by the other methods.
+
+Generally you won't need to construct a resultset manually. You'll
+automatically get one from e.g. a L</search> called in scalar context:
+
+ my $rs = $schema->resultset('CD')->search({ title => '100th Window' });
=cut
sub new {
- my ($class, $source, $attrs) = @_;
- #use Data::Dumper; warn Dumper(@_);
- $class = ref $class if ref $class;
- $attrs = { %{ $attrs || {} } };
- my %seen;
- if (!$attrs->{select}) {
- my @cols = ($attrs->{cols}
- ? @{delete $attrs->{cols}}
- : $source->result_class->_select_columns);
- $attrs->{select} = [ map { m/\./ ? $_ : "me.$_" } @cols ];
+ my $class = shift;
+ return $class->new_result(@_) if ref $class;
+
+ my ($source, $attrs) = @_;
+ weaken $source;
+ $attrs = Storable::dclone($attrs || {}); # { %{ $attrs || {} } };
+ #use Data::Dumper; warn Dumper($attrs);
+ my $alias = ($attrs->{alias} ||= 'me');
+
+ $attrs->{columns} ||= delete $attrs->{cols} if $attrs->{cols};
+ delete $attrs->{as} if $attrs->{columns};
+ $attrs->{columns} ||= [ $source->columns ] unless $attrs->{select};
+ $attrs->{select} = [
+ map { m/\./ ? $_ : "${alias}.$_" } @{delete $attrs->{columns}}
+ ] if $attrs->{columns};
+ $attrs->{as} ||= [
+ map { m/^\Q$alias.\E(.+)$/ ? $1 : $_ } @{$attrs->{select}}
+ ];
+ if (my $include = delete $attrs->{include_columns}) {
+ push(@{$attrs->{select}}, @$include);
+ push(@{$attrs->{as}}, map { m/([^.]+)$/; $1; } @$include);
}
- $attrs->{as} ||= [ map { m/^me\.(.*)$/ ? $1 : $_ } @{$attrs->{select}} ];
#use Data::Dumper; warn Dumper(@{$attrs}{qw/select as/});
- $attrs->{from} ||= [ { 'me' => $source->name } ];
+
+ $attrs->{from} ||= [ { $alias => $source->from } ];
+ $attrs->{seen_join} ||= {};
+ my %seen;
if (my $join = delete $attrs->{join}) {
- foreach my $j (ref $join eq 'ARRAY'
- ? (@{$join}) : ($join)) {
+ foreach my $j (ref $join eq 'ARRAY' ? @$join : ($join)) {
if (ref $j eq 'HASH') {
$seen{$_} = 1 foreach keys %$j;
} else {
$seen{$j} = 1;
}
}
- push(@{$attrs->{from}}, $source->result_class->_resolve_join($join, 'me'));
+ push(@{$attrs->{from}}, $source->resolve_join(
+ $join, $attrs->{alias}, $attrs->{seen_join})
+ );
}
+
$attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct};
- foreach my $pre (@{delete $attrs->{prefetch} || []}) {
- push(@{$attrs->{from}}, $source->result_class->_resolve_join($pre, 'me'))
- unless $seen{$pre};
- my @pre =
- map { "$pre.$_" }
- $source->result_class->_relationships->{$pre}->{class}->columns;
- push(@{$attrs->{select}}, @pre);
- push(@{$attrs->{as}}, @pre);
+ $attrs->{order_by} = [ $attrs->{order_by} ] if
+ $attrs->{order_by} and !ref($attrs->{order_by});
+ $attrs->{order_by} ||= [];
+
+ my $collapse = $attrs->{collapse} || {};
+ if (my $prefetch = delete $attrs->{prefetch}) {
+ my @pre_order;
+ foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) {
+ if ( ref $p eq 'HASH' ) {
+ foreach my $key (keys %$p) {
+ push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias}))
+ unless $seen{$key};
+ }
+ } else {
+ push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias}))
+ unless $seen{$p};
+ }
+ my @prefetch = $source->resolve_prefetch(
+ $p, $attrs->{alias}, {}, \@pre_order, $collapse);
+ push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
+ push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
+ }
+ push(@{$attrs->{order_by}}, @pre_order);
+ }
+ $attrs->{collapse} = $collapse;
+# use Data::Dumper; warn Dumper($collapse) if keys %{$collapse};
+
+ if ($attrs->{page}) {
+ $attrs->{rows} ||= 10;
+ $attrs->{offset} ||= 0;
+ $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1));
}
- my $new = {
- source => $source,
+
+ bless {
+ result_source => $source,
+ result_class => $attrs->{result_class} || $source->result_class,
cond => $attrs->{where},
from => $attrs->{from},
+ collapse => $collapse,
count => undef,
+ page => delete $attrs->{page},
pager => undef,
- attrs => $attrs };
- bless ($new, $class);
- $new->pager if $attrs->{page};
- return $new;
+ attrs => $attrs
+ }, $class;
}
=head2 search
- my @obj = $rs->search({ foo => 3 }); # "... WHERE foo = 3"
- my $new_rs = $rs->search({ foo => 3 });
-
+ my @cds = $rs->search({ year => 2001 }); # "... WHERE year = 2001"
+ my $new_rs = $rs->search({ year => 2005 });
+
If you need to pass in additional attributes but no additional condition,
-call it as ->search(undef, \%attrs);
-
- my @all = $class->search({}, { cols => [qw/foo bar/] }); # "SELECT foo, bar FROM $class_table"
+call it as C<search(undef, \%attrs);>.
+
+ # "SELECT name, artistid FROM $artist_table"
+ my @all_artists = $schema->resultset('Artist')->search(undef, {
+ columns => [qw/name artistid/],
+ });
=cut
sub search {
my $self = shift;
- #use Data::Dumper;warn Dumper(@_);
-
- my $attrs = { %{$self->{attrs}} };
- if (@_ > 1 && ref $_[$#_] eq 'HASH') {
- $attrs = { %{ pop(@_) } };
- }
-
- my $where = ((@_ == 1 || ref $_[0] eq "HASH") ? shift : {@_});
- if (defined $where) {
- $where = (defined $attrs->{where}
- ? { '-and' => [ $where, $attrs->{where} ] }
+ my $rs;
+ if( @_ ) {
+
+ my $attrs = { %{$self->{attrs}} };
+ my $having = delete $attrs->{having};
+ $attrs = { %$attrs, %{ pop(@_) } } if @_ > 1 and ref $_[$#_] eq 'HASH';
+
+ my $where = (@_
+ ? ((@_ == 1 || ref $_[0] eq "HASH")
+ ? shift
+ : ((@_ % 2)
+ ? $self->throw_exception(
+ "Odd number of arguments to search")
+ : {@_}))
+ : undef());
+ if (defined $where) {
+ $attrs->{where} = (defined $attrs->{where}
+ ? { '-and' =>
+ [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
+ $where, $attrs->{where} ] }
: $where);
- $attrs->{where} = $where;
- }
+ }
- my $rs = $self->new($self->{source}, $attrs);
+ if (defined $having) {
+ $attrs->{having} = (defined $attrs->{having}
+ ? { '-and' =>
+ [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
+ $having, $attrs->{having} ] }
+ : $having);
+ }
+ $rs = (ref $self)->new($self->result_source, $attrs);
+ }
+ else {
+ $rs = $self;
+ $rs->reset;
+ }
return (wantarray ? $rs->all : $rs);
}
-=head2 search_literal
+=head2 search_literal
+
my @obj = $rs->search_literal($literal_where_cond, @bind);
my $new_rs = $rs->search_literal($literal_where_cond, @bind);
Pass a literal chunk of SQL to be added to the conditional part of the
-resultset
+resultset.
=cut
-
+
sub search_literal {
my ($self, $cond, @vals) = @_;
my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
return $self->search(\$cond, $attrs);
}
+=head2 find
+
+=over 4
+
+=item Arguments: (@colvalues) | (\%cols, \%attrs?)
+
+=back
+
+Finds a row based on its primary key or unique constraint. For example:
+
+ my $cd = $schema->resultset('CD')->find(5);
+
+Also takes an optional C<key> attribute, to search by a specific key or unique
+constraint. For example:
+
+ my $cd = $schema->resultset('CD')->find(
+ {
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ },
+ { key => 'artist_title' }
+ );
+
+See also L</find_or_create> and L</update_or_create>.
+
+=cut
+
+sub find {
+ my ($self, @vals) = @_;
+ my $attrs = (@vals > 1 && ref $vals[$#vals] eq 'HASH' ? pop(@vals) : {});
+
+ my @cols = $self->result_source->primary_columns;
+ if (exists $attrs->{key}) {
+ my %uniq = $self->result_source->unique_constraints;
+ $self->throw_exception(
+ "Unknown key $attrs->{key} on '" . $self->result_source->name . "'"
+ ) unless exists $uniq{$attrs->{key}};
+ @cols = @{ $uniq{$attrs->{key}} };
+ }
+ #use Data::Dumper; warn Dumper($attrs, @vals, @cols);
+ $self->throw_exception(
+ "Can't find unless a primary key or unique constraint is defined"
+ ) unless @cols;
+
+ my $query;
+ if (ref $vals[0] eq 'HASH') {
+ $query = { %{$vals[0]} };
+ } elsif (@cols == @vals) {
+ $query = {};
+ @{$query}{@cols} = @vals;
+ } else {
+ $query = {@vals};
+ }
+ foreach my $key (grep { ! m/\./ } keys %$query) {
+ $query->{"$self->{attrs}{alias}.$key"} = delete $query->{$key};
+ }
+ #warn Dumper($query);
+
+ if (keys %$attrs) {
+ my $rs = $self->search($query,$attrs);
+ return keys %{$rs->{collapse}} ? $rs->next : $rs->single;
+ } else {
+ return keys %{$self->{collapse}} ?
+ $self->search($query)->next :
+ $self->single($query);
+ }
+}
+
=head2 search_related
$rs->search_related('relname', $cond?, $attrs?);
+Search the specified relationship. Optionally specify a condition for matching
+records.
+
=cut
-sub search_related { }
+sub search_related {
+ return shift->related_resultset(shift)->search(@_);
+}
=head2 cursor
sub cursor {
my ($self) = @_;
- my ($source, $attrs) = @{$self}{qw/source attrs/};
- if ($attrs->{page}) {
- $attrs->{rows} = $self->pager->entries_per_page;
- $attrs->{offset} = $self->pager->skipped;
- }
+ my $attrs = { %{$self->{attrs}} };
return $self->{cursor}
- ||= $source->storage->select($self->{from}, $attrs->{select},
+ ||= $self->result_source->storage->select($self->{from}, $attrs->{select},
$attrs->{where},$attrs);
}
-=head2 search_like
-
-Identical to search except defaults to 'LIKE' instead of '=' in condition
-
-=cut
+=head2 single
-sub search_like {
- my $class = shift;
- my $attrs = { };
- if (@_ > 1 && ref $_[$#_] eq 'HASH') {
- $attrs = pop(@_);
+Inflates the first result without creating a cursor
+
+=cut
+
+sub single {
+ my ($self, $where) = @_;
+ my $attrs = { %{$self->{attrs}} };
+ if ($where) {
+ if (defined $attrs->{where}) {
+ $attrs->{where} = {
+ '-and' =>
+ [ map { ref $_ eq 'ARRAY' ? [ -or => $_ ] : $_ }
+ $where, delete $attrs->{where} ]
+ };
+ } else {
+ $attrs->{where} = $where;
+ }
}
- my $query = ref $_[0] eq "HASH" ? { %{shift()} }: {@_};
+ my @data = $self->result_source->storage->select_single(
+ $self->{from}, $attrs->{select},
+ $attrs->{where},$attrs);
+ return (@data ? $self->_construct_object(@data) : ());
+}
+
+
+=head2 search_like
+
+Perform a search, but use C<LIKE> instead of equality as the condition. Note
+that this is simply a convenience method; you most likely want to use
+L</search> with specific operators.
+
+For more information, see L<DBIx::Class::Manual::Cookbook>.
+
+=cut
+
+sub search_like {
+ my $class = shift;
+ my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
+ my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
$query->{$_} = { 'like' => $query->{$_} } for keys %$query;
return $class->search($query, { %$attrs });
}
-=head2 slice($first, $last)
+=head2 slice
+
+=over 4
+
+=item Arguments: ($first, $last)
+
+=back
Returns a subset of elements from the resultset.
sub slice {
my ($self, $min, $max) = @_;
my $attrs = { %{ $self->{attrs} || {} } };
- $self->{source}->result_class->throw("Can't slice without where") unless $attrs->{where};
- $attrs->{offset} = $min;
+ $attrs->{offset} ||= 0;
+ $attrs->{offset} += $min;
$attrs->{rows} = ($max ? ($max - $min + 1) : 1);
- my $slice = $self->new($self->{source}, $attrs);
+ my $slice = (ref $self)->new($self->result_source, $attrs);
return (wantarray ? $slice->all : $slice);
}
-=head2 next
+=head2 next
-Returns the next element in the resultset (undef is there is none).
+Returns the next element in the resultset (C<undef> is there is none).
+
+Can be used to efficiently iterate over records in the resultset:
+
+ my $rs = $schema->resultset('CD')->search;
+ while (my $cd = $rs->next) {
+ print $cd->title;
+ }
=cut
sub next {
my ($self) = @_;
- my @row = $self->cursor->next;
+ if (@{$self->{all_cache} || []}) {
+ $self->{all_cache_position} ||= 0;
+ return $self->{all_cache}->[$self->{all_cache_position}++];
+ }
+ if ($self->{attrs}{cache}) {
+ $self->{all_cache_position} = 1;
+ return ($self->all)[0];
+ }
+ my @row = (exists $self->{stashed_row} ?
+ @{delete $self->{stashed_row}} :
+ $self->cursor->next
+ );
+# warn Dumper(\@row); use Data::Dumper;
return unless (@row);
return $self->_construct_object(@row);
}
sub _construct_object {
my ($self, @row) = @_;
- my @cols = @{ $self->{attrs}{as} };
- #warn "@cols -> @row";
- my (%me, %pre);
- foreach my $col (@cols) {
- if ($col =~ /([^\.]+)\.([^\.]+)/) {
- $pre{$1}{$2} = shift @row;
- } else {
- $me{$col} = shift @row;
- }
- }
- my $new = $self->{source}->result_class->inflate_result(\%me, \%pre);
+ my @as = @{ $self->{attrs}{as} };
+
+ my $info = $self->_collapse_result(\@as, \@row);
+
+ my $new = $self->result_class->inflate_result($self->result_source, @$info);
+
$new = $self->{attrs}{record_filter}->($new)
if exists $self->{attrs}{record_filter};
return $new;
}
+sub _collapse_result {
+ my ($self, $as, $row, $prefix) = @_;
+
+ my %const;
+
+ my @copy = @$row;
+ foreach my $this_as (@$as) {
+ my $val = shift @copy;
+ if (defined $prefix) {
+ if ($this_as =~ m/^\Q${prefix}.\E(.+)$/) {
+ my $remain = $1;
+ $remain =~ /^(?:(.*)\.)?([^.]+)$/;
+ $const{$1||''}{$2} = $val;
+ }
+ } else {
+ $this_as =~ /^(?:(.*)\.)?([^.]+)$/;
+ $const{$1||''}{$2} = $val;
+ }
+ }
+
+ my $info = [ {}, {} ];
+ foreach my $key (keys %const) {
+ if (length $key) {
+ my $target = $info;
+ my @parts = split(/\./, $key);
+ foreach my $p (@parts) {
+ $target = $target->[1]->{$p} ||= [];
+ }
+ $target->[0] = $const{$key};
+ } else {
+ $info->[0] = $const{$key};
+ }
+ }
+
+ my @collapse;
+ if (defined $prefix) {
+ @collapse = map {
+ m/^\Q${prefix}.\E(.+)$/ ? ($1) : ()
+ } keys %{$self->{collapse}}
+ } else {
+ @collapse = keys %{$self->{collapse}};
+ };
+
+ if (@collapse) {
+ my ($c) = sort { length $a <=> length $b } @collapse;
+ my $target = $info;
+ foreach my $p (split(/\./, $c)) {
+ $target = $target->[1]->{$p} ||= [];
+ }
+ my $c_prefix = (defined($prefix) ? "${prefix}.${c}" : $c);
+ my @co_key = @{$self->{collapse}{$c_prefix}};
+ my %co_check = map { ($_, $target->[0]->{$_}); } @co_key;
+ my $tree = $self->_collapse_result($as, $row, $c_prefix);
+ my (@final, @raw);
+ while ( !(grep {
+ !defined($tree->[0]->{$_}) ||
+ $co_check{$_} ne $tree->[0]->{$_}
+ } @co_key) ) {
+ push(@final, $tree);
+ last unless (@raw = $self->cursor->next);
+ $row = $self->{stashed_row} = \@raw;
+ $tree = $self->_collapse_result($as, $row, $c_prefix);
+ #warn Data::Dumper::Dumper($tree, $row);
+ }
+ @$target = @final;
+ }
+
+ return $info;
+}
+
+=head2 result_source
+
+Returns a reference to the result source for this recordset.
+
+=cut
+
+
=head2 count
Performs an SQL C<COUNT> with the same query as the resultset was built
with to find the number of elements. If passed arguments, does a search
on the resultset and counts the results of that.
+Note: When using C<count> with C<group_by>, L<DBIX::Class> emulates C<GROUP BY>
+using C<COUNT( DISTINCT( columns ) )>. Some databases (notably SQLite) do
+not support C<DISTINCT> with multiple columns. If you are using such a
+database, you should only use columns from the main table in your C<group_by>
+clause.
+
=cut
sub count {
my $self = shift;
- return $self->search(@_)->count if @_ && defined $_[0];
- die "Unable to ->count with a GROUP BY" if defined $self->{attrs}{group_by};
- unless ($self->{count}) {
- my $attrs = { %{ $self->{attrs} },
- select => { 'count' => '*' },
- as => [ 'count' ] };
- # offset and order by are not needed to count, page, join and prefetch
- # will get in the way (add themselves to from again ...)
- delete $attrs->{$_} for qw/offset order_by page join prefetch/;
-
- my @cols = 'COUNT(*)';
- ($self->{count}) = $self->search(undef, $attrs)->cursor->next;
+ return $self->search(@_)->count if @_ and defined $_[0];
+ return scalar @{ $self->get_cache } if @{ $self->get_cache };
+
+ my $count = $self->_count;
+ return 0 unless $count;
+
+ $count -= $self->{attrs}{offset} if $self->{attrs}{offset};
+ $count = $self->{attrs}{rows} if
+ $self->{attrs}{rows} and $self->{attrs}{rows} < $count;
+ return $count;
+}
+
+sub _count { # Separated out so pager can get the full count
+ my $self = shift;
+ my $select = { count => '*' };
+ my $attrs = { %{ $self->{attrs} } };
+ if (my $group_by = delete $attrs->{group_by}) {
+ delete $attrs->{having};
+ my @distinct = (ref $group_by ? @$group_by : ($group_by));
+ # todo: try CONCAT for multi-column pk
+ my @pk = $self->result_source->primary_columns;
+ if (@pk == 1) {
+ foreach my $column (@distinct) {
+ if ($column =~ qr/^(?:\Q$attrs->{alias}.\E)?$pk[0]$/) {
+ @distinct = ($column);
+ last;
+ }
+ }
+ }
+
+ $select = { count => { distinct => \@distinct } };
+ #use Data::Dumper; die Dumper $select;
}
- return 0 unless $self->{count};
- return $self->{pager}->entries_on_this_page if ($self->{pager});
- return ( $self->{attrs}->{rows} && $self->{attrs}->{rows} < $self->{count} )
- ? $self->{attrs}->{rows}
- : $self->{count};
+
+ $attrs->{select} = $select;
+ $attrs->{as} = [qw/count/];
+
+ # offset, order by and page are not needed to count. record_filter is cdbi
+ delete $attrs->{$_} for qw/rows offset order_by page pager record_filter/;
+
+ my ($count) = (ref $self)->new($self->result_source, $attrs)->cursor->next;
+ return $count;
}
=head2 count_literal
-Calls search_literal with the passed arguments, then count.
+Calls L</search_literal> with the passed arguments, then L</count>.
=cut
=head2 all
-Returns all elements in the resultset. Called implictly if the resultset
+Returns all elements in the resultset. Called implicitly if the resultset
is returned in list context.
=cut
sub all {
my ($self) = @_;
- return map { $self->_construct_object(@$_); }
- $self->cursor->all;
+ return @{ $self->get_cache } if @{ $self->get_cache };
+
+ my @obj;
+
+ if (keys %{$self->{collapse}}) {
+ # Using $self->cursor->all is really just an optimisation.
+ # If we're collapsing has_many prefetches it probably makes
+ # very little difference, and this is cleaner than hacking
+ # _construct_object to survive the approach
+ $self->cursor->reset;
+ my @row = $self->cursor->next;
+ while (@row) {
+ push(@obj, $self->_construct_object(@row));
+ @row = (exists $self->{stashed_row}
+ ? @{delete $self->{stashed_row}}
+ : $self->cursor->next);
+ }
+ } else {
+ @obj = map { $self->_construct_object(@$_) } $self->cursor->all;
+ }
+
+ $self->set_cache(\@obj) if $self->{attrs}{cache};
+ return @obj;
}
=head2 reset
sub reset {
my ($self) = @_;
+ $self->{all_cache_position} = 0;
$self->cursor->reset;
return $self;
}
return $_[0]->reset->next;
}
+=head2 update
+
+=over 4
+
+=item Arguments: (\%values)
+
+=back
+
+Sets the specified columns in the resultset to the supplied values.
+
+=cut
+
+sub update {
+ my ($self, $values) = @_;
+ $self->throw_exception("Values for update must be a hash")
+ unless ref $values eq 'HASH';
+ return $self->result_source->storage->update(
+ $self->result_source->from, $values, $self->{cond}
+ );
+}
+
+=head2 update_all
+
+=over 4
+
+=item Arguments: (\%values)
+
+=back
+
+Fetches all objects and updates them one at a time. Note that C<update_all>
+will run cascade triggers while L</update> will not.
+
+=cut
+
+sub update_all {
+ my ($self, $values) = @_;
+ $self->throw_exception("Values for update must be a hash")
+ unless ref $values eq 'HASH';
+ foreach my $obj ($self->all) {
+ $obj->set_columns($values)->update;
+ }
+ return 1;
+}
+
=head2 delete
-Deletes all elements in the resultset.
+Deletes the contents of the resultset from its result source.
=cut
sub delete {
my ($self) = @_;
- $_->delete for $self->all;
+ my $del = {};
+
+ if (!ref($self->{cond})) {
+
+ # No-op. No condition, we're deleting everything
+
+ } elsif (ref $self->{cond} eq 'ARRAY') {
+
+ $del = [ map { my %hash;
+ foreach my $key (keys %{$_}) {
+ $key =~ /([^.]+)$/;
+ $hash{$1} = $_->{$key};
+ }; \%hash; } @{$self->{cond}} ];
+
+ } elsif (ref $self->{cond} eq 'HASH') {
+
+ if ((keys %{$self->{cond}})[0] eq '-and') {
+
+ $del->{-and} = [ map { my %hash;
+ foreach my $key (keys %{$_}) {
+ $key =~ /([^.]+)$/;
+ $hash{$1} = $_->{$key};
+ }; \%hash; } @{$self->{cond}{-and}} ];
+
+ } else {
+
+ foreach my $key (keys %{$self->{cond}}) {
+ $key =~ /([^.]+)$/;
+ $del->{$1} = $self->{cond}{$key};
+ }
+ }
+
+ } else {
+ $self->throw_exception(
+ "Can't delete on resultset with condition unless hash or array"
+ );
+ }
+
+ $self->result_source->storage->delete($self->result_source->from, $del);
return 1;
}
-*delete_all = \&delete; # Yeah, yeah, yeah ...
+=head2 delete_all
+
+Fetches all objects and deletes them one at a time. Note that C<delete_all>
+will run cascade triggers while L</delete> will not.
+
+=cut
+
+sub delete_all {
+ my ($self) = @_;
+ $_->delete for $self->all;
+ return 1;
+}
=head2 pager
Returns a L<Data::Page> object for the current resultset. Only makes
-sense for queries with page turned on.
+sense for queries with a C<page> attribute.
=cut
sub pager {
my ($self) = @_;
my $attrs = $self->{attrs};
- delete $attrs->{offset};
- my $rows_per_page = delete $attrs->{rows} || 10;
- $self->{pager} ||= Data::Page->new(
- $self->count, $rows_per_page, $attrs->{page} || 1);
- $attrs->{rows} = $rows_per_page;
- return $self->{pager};
+ $self->throw_exception("Can't create pager for non-paged rs")
+ unless $self->{page};
+ $attrs->{rows} ||= 10;
+ return $self->{pager} ||= Data::Page->new(
+ $self->_count, $attrs->{rows}, $self->{page});
}
-=head2 page($page_num)
+=head2 page
+
+=over 4
+
+=item Arguments: ($page_num)
+
+=back
Returns a new resultset for the specified page.
sub page {
my ($self, $page) = @_;
- my $attrs = $self->{attrs};
+ my $attrs = { %{$self->{attrs}} };
$attrs->{page} = $page;
- return $self->new($self->{source}, $attrs);
+ return (ref $self)->new($self->result_source, $attrs);
}
-=head1 Attributes
+=head2 new_result
+
+=over 4
+
+=item Arguments: (\%vals)
+
+=back
+
+Creates a result in the resultset's result class.
+
+=cut
+
+sub new_result {
+ my ($self, $values) = @_;
+ $self->throw_exception( "new_result needs a hash" )
+ unless (ref $values eq 'HASH');
+ $self->throw_exception(
+ "Can't abstract implicit construct, condition not a hash"
+ ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH'));
+ my %new = %$values;
+ my $alias = $self->{attrs}{alias};
+ foreach my $key (keys %{$self->{cond}||{}}) {
+ $new{$1} = $self->{cond}{$key} if ($key =~ m/^(?:\Q${alias}.\E)?([^.]+)$/);
+ }
+ my $obj = $self->result_class->new(\%new);
+ $obj->result_source($self->result_source) if $obj->can('result_source');
+ return $obj;
+}
+
+=head2 create
+
+=over 4
+
+=item Arguments: (\%vals)
+
+=back
+
+Inserts a record into the resultset and returns the object.
+
+Effectively a shortcut for C<< ->new_result(\%vals)->insert >>.
+
+=cut
+
+sub create {
+ my ($self, $attrs) = @_;
+ $self->throw_exception( "create needs a hashref" )
+ unless ref $attrs eq 'HASH';
+ return $self->new_result($attrs)->insert;
+}
+
+=head2 find_or_create
+
+=over 4
+
+=item Arguments: (\%vals, \%attrs?)
+
+=back
+
+ $class->find_or_create({ key => $val, ... });
-The resultset takes various attributes that modify its behavior.
-Here's an overview of them:
+Searches for a record matching the search condition; if it doesn't find one,
+creates one and returns that instead.
+
+ my $cd = $schema->resultset('CD')->find_or_create({
+ cdid => 5,
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ year => 2005,
+ });
+
+Also takes an optional C<key> attribute, to search by a specific key or unique
+constraint. For example:
+
+ my $cd = $schema->resultset('CD')->find_or_create(
+ {
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ },
+ { key => 'artist_title' }
+ );
+
+See also L</find> and L</update_or_create>.
+
+=cut
+
+sub find_or_create {
+ my $self = shift;
+ my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
+ my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
+ my $exists = $self->find($hash, $attrs);
+ return defined $exists ? $exists : $self->create($hash);
+}
+
+=head2 update_or_create
+
+ $class->update_or_create({ key => $val, ... });
+
+First, search for an existing row matching one of the unique constraints
+(including the primary key) on the source of this resultset. If a row is
+found, update it with the other given column values. Otherwise, create a new
+row.
+
+Takes an optional C<key> attribute to search on a specific unique constraint.
+For example:
+
+ # In your application
+ my $cd = $schema->resultset('CD')->update_or_create(
+ {
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ year => 1998,
+ },
+ { key => 'artist_title' }
+ );
+
+If no C<key> is specified, it searches on all unique constraints defined on the
+source, including the primary key.
+
+If the C<key> is specified as C<primary>, search only on the primary key.
+
+See also L</find> and L</find_or_create>.
+
+=cut
+
+sub update_or_create {
+ my $self = shift;
+ my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
+ my $hash = ref $_[0] eq 'HASH' ? shift : {@_};
+
+ my %unique_constraints = $self->result_source->unique_constraints;
+ my @constraint_names = (exists $attrs->{key}
+ ? ($attrs->{key})
+ : keys %unique_constraints);
+
+ my @unique_hashes;
+ foreach my $name (@constraint_names) {
+ my @unique_cols = @{ $unique_constraints{$name} };
+ my %unique_hash =
+ map { $_ => $hash->{$_} }
+ grep { exists $hash->{$_} }
+ @unique_cols;
+
+ push @unique_hashes, \%unique_hash
+ if (scalar keys %unique_hash == scalar @unique_cols);
+ }
+
+ if (@unique_hashes) {
+ my $row = $self->single(\@unique_hashes);
+ if (defined $row) {
+ $row->set_columns($hash);
+ $row->update;
+ return $row;
+ }
+ }
+
+ return $self->create($hash);
+}
+
+=head2 get_cache
+
+Gets the contents of the cache for the resultset.
+
+=cut
+
+sub get_cache {
+ shift->{all_cache} || [];
+}
+
+=head2 set_cache
+
+Sets the contents of the cache for the resultset. Expects an arrayref
+of objects of the same class as those produced by the resultset.
+
+=cut
+
+sub set_cache {
+ my ( $self, $data ) = @_;
+ $self->throw_exception("set_cache requires an arrayref")
+ if ref $data ne 'ARRAY';
+ my $result_class = $self->result_class;
+ foreach( @$data ) {
+ $self->throw_exception(
+ "cannot cache object of type '$_', expected '$result_class'"
+ ) if ref $_ ne $result_class;
+ }
+ $self->{all_cache} = $data;
+}
+
+=head2 clear_cache
+
+Clears the cache for the resultset.
+
+=cut
+
+sub clear_cache {
+ shift->set_cache([]);
+}
+
+=head2 related_resultset
+
+Returns a related resultset for the supplied relationship name.
+
+ $artist_rs = $schema->resultset('CD')->related_resultset('Artist');
+
+=cut
+
+sub related_resultset {
+ my ( $self, $rel, @rest ) = @_;
+ $self->{related_resultsets} ||= {};
+ return $self->{related_resultsets}{$rel} ||= do {
+ #warn "fetching related resultset for rel '$rel'";
+ my $rel_obj = $self->result_source->relationship_info($rel);
+ $self->throw_exception(
+ "search_related: result source '" . $self->result_source->name .
+ "' has no such relationship ${rel}")
+ unless $rel_obj; #die Dumper $self->{attrs};
+
+ my $rs = $self->search(undef, { join => $rel });
+ my $alias = defined $rs->{attrs}{seen_join}{$rel}
+ && $rs->{attrs}{seen_join}{$rel} > 1
+ ? join('_', $rel, $rs->{attrs}{seen_join}{$rel})
+ : $rel;
+
+ $self->result_source->schema->resultset($rel_obj->{class}
+ )->search( undef,
+ { %{$rs->{attrs}},
+ alias => $alias,
+ select => undef,
+ as => undef }
+ )->search(@rest);
+ };
+}
+
+=head2 throw_exception
+
+See Schema's throw_exception
+
+=cut
+
+sub throw_exception {
+ my $self=shift;
+ $self->result_source->schema->throw_exception(@_);
+}
+
+=head1 ATTRIBUTES
+
+XXX: FIXME: Attributes docs need clearing up
+
+The resultset takes various attributes that modify its behavior. Here's an
+overview of them:
=head2 order_by
Which column(s) to order the results by. This is currently passed
-through directly to SQL, so you can give e.g. C<foo DESC> for a
-descending order.
+through directly to SQL, so you can give e.g. C<year DESC> for a
+descending order on the column `year'.
+
+=head2 columns
+
+=over 4
+
+=item Arguments: (\@columns)
+
+=back
+
+Shortcut to request a particular set of columns to be retrieved. Adds
+C<me.> onto the start of any column without a C<.> in it and sets C<select>
+from that, then auto-populates C<as> from C<select> as normal. (You may also
+use the C<cols> attribute, as in earlier versions of DBIC.)
+
+=head2 include_columns
+
+=over 4
+
+=item Arguments: (\@columns)
+
+=back
+
+Shortcut to include additional columns in the returned results - for example
+
+ $schema->resultset('CD')->search(undef, {
+ include_columns => ['artist.name'],
+ join => ['artist']
+ });
+
+would return all CDs and include a 'name' column to the information
+passed to object inflation
+
+=head2 select
+
+=over 4
+
+=item Arguments: (\@columns)
-=head2 cols (arrayref)
+=back
-Shortcut to request a particular set of columns to be retrieved - adds
-'me.' onto the start of any column without a '.' in it and sets 'select'
-from that, then auto-populates 'as' from 'select' as normal
+Indicates which columns should be selected from the storage. You can use
+column names, or in the case of RDBMS back ends, function or stored procedure
+names:
-=head2 select (arrayref)
+ $rs = $schema->resultset('Employee')->search(undef, {
+ select => [
+ 'name',
+ { count => 'employeeid' },
+ { sum => 'salary' }
+ ]
+ });
-Indicates which columns should be selected from the storage
+When you use function/stored procedure names and do not supply an C<as>
+attribute, the column names returned are storage-dependent. E.g. MySQL would
+return a column named C<count(employeeid)> in the above example.
-=head2 as (arrayref)
+=head2 as
-Indicates column names for object inflation
+=over 4
+
+=item Arguments: (\@names)
+
+=back
+
+Indicates column names for object inflation. This is used in conjunction with
+C<select>, usually when C<select> contains one or more function or stored
+procedure names:
+
+ $rs = $schema->resultset('Employee')->search(undef, {
+ select => [
+ 'name',
+ { count => 'employeeid' }
+ ],
+ as => ['name', 'employee_count'],
+ });
+
+ my $employee = $rs->first(); # get the first Employee
+
+If the object against which the search is performed already has an accessor
+matching a column name specified in C<as>, the value can be retrieved using
+the accessor as normal:
+
+ my $name = $employee->name();
+
+If on the other hand an accessor does not exist in the object, you need to
+use C<get_column> instead:
+
+ my $employee_count = $employee->get_column('employee_count');
+
+You can create your own accessors if required - see
+L<DBIx::Class::Manual::Cookbook> for details.
=head2 join
-Contains a list of relationships that should be joined for this query. Can also
-contain a hash reference to refer to that relation's relations. So, if one column
-in your class C<belongs_to> foo and another C<belongs_to> bar, you can do
-C<< join => [qw/ foo bar /] >> to join both (and e.g. use them for C<order_by>).
-If a foo contains many margles and you want to join those too, you can do
-C<< join => { foo => 'margle' } >>. If you want to fetch the columns from the
-related table as well, see C<prefetch> below.
+Contains a list of relationships that should be joined for this query. For
+example:
+
+ # Get CDs by Nine Inch Nails
+ my $rs = $schema->resultset('CD')->search(
+ { 'artist.name' => 'Nine Inch Nails' },
+ { join => 'artist' }
+ );
+
+Can also contain a hash reference to refer to the other relation's relations.
+For example:
+
+ package MyApp::Schema::Track;
+ use base qw/DBIx::Class/;
+ __PACKAGE__->table('track');
+ __PACKAGE__->add_columns(qw/trackid cd position title/);
+ __PACKAGE__->set_primary_key('trackid');
+ __PACKAGE__->belongs_to(cd => 'MyApp::Schema::CD');
+ 1;
+
+ # In your application
+ my $rs = $schema->resultset('Artist')->search(
+ { 'track.title' => 'Teardrop' },
+ {
+ join => { cd => 'track' },
+ order_by => 'artist.name',
+ }
+ );
+
+If the same join is supplied twice, it will be aliased to <rel>_2 (and
+similarly for a third time). For e.g.
+
+ my $rs = $schema->resultset('Artist')->search({
+ 'cds.title' => 'Down to Earth',
+ 'cds_2.title' => 'Popular',
+ }, {
+ join => [ qw/cds cds/ ],
+ });
+
+will return a set of all artists that have both a cd with title 'Down
+to Earth' and a cd with title 'Popular'.
+
+If you want to fetch related objects from other tables as well, see C<prefetch>
+below.
=head2 prefetch
-Contains a list of relationships that should be fetched along with the main
-query (when they are accessed afterwards they will have already been
-"prefetched"). This is useful for when you know you will need the related
-object(s), because it saves a query. Currently limited to prefetching
-one relationship deep, so unlike C<join>, prefetch must be an arrayref.
+=over 4
-=head2 from
+=item Arguments: (\@relationships)
-This attribute can contain a arrayref of elements. Each element can be another
-arrayref, to nest joins, or it can be a hash which represents the two sides
-of the join.
+=back
-NOTE: Use this on your own risk. This allows you to shoot your foot off!
+Contains one or more relationships that should be fetched along with the main
+query (when they are accessed afterwards they will have already been
+"prefetched"). This is useful for when you know you will need the related
+objects, because it saves at least one query:
+
+ my $rs = $schema->resultset('Tag')->search(
+ undef,
+ {
+ prefetch => {
+ cd => 'artist'
+ }
+ }
+ );
+
+The initial search results in SQL like the following:
+
+ SELECT tag.*, cd.*, artist.* FROM tag
+ JOIN cd ON tag.cd = cd.cdid
+ JOIN artist ON cd.artist = artist.artistid
+
+L<DBIx::Class> has no need to go back to the database when we access the
+C<cd> or C<artist> relationships, which saves us two SQL statements in this
+case.
+
+Simple prefetches will be joined automatically, so there is no need
+for a C<join> attribute in the above search. If you're prefetching to
+depth (e.g. { cd => { artist => 'label' } or similar), you'll need to
+specify the join as well.
+
+C<prefetch> can be used with the following relationship types: C<belongs_to>,
+C<has_one> (or if you're using C<add_relationship>, any relationship declared
+with an accessor type of 'single' or 'filter').
+
+=head2 from
+
+=over 4
+
+=item Arguments: (\@array)
+
+=back
+
+The C<from> attribute gives you manual control over the C<FROM> clause of SQL
+statements generated by L<DBIx::Class>, allowing you to express custom C<JOIN>
+clauses.
+
+NOTE: Use this on your own risk. This allows you to shoot off your foot!
+C<join> will usually do what you need and it is strongly recommended that you
+avoid using C<from> unless you cannot achieve the desired result using C<join>.
+
+In simple terms, C<from> works as follows:
+
+ [
+ { <alias> => <table>, -join-type => 'inner|left|right' }
+ [] # nested JOIN (optional)
+ { <table.column> = <foreign_table.foreign_key> }
+ ]
+
+ JOIN
+ <alias> <table>
+ [JOIN ...]
+ ON <table.column> = <foreign_table.foreign_key>
+
+An easy way to follow the examples below is to remember the following:
+
+ Anything inside "[]" is a JOIN
+ Anything inside "{}" is a condition for the enclosing JOIN
+
+The following examples utilize a "person" table in a family tree application.
+In order to express parent->child relationships, this table is self-joined:
+
+ # Person->belongs_to('father' => 'Person');
+ # Person->belongs_to('mother' => 'Person');
+
+C<from> can be used to nest joins. Here we return all children with a father,
+then search against all mothers of those children:
+
+ $rs = $schema->resultset('Person')->search(
+ undef,
+ {
+ alias => 'mother', # alias columns in accordance with "from"
+ from => [
+ { mother => 'person' },
+ [
+ [
+ { child => 'person' },
+ [
+ { father => 'person' },
+ { 'father.person_id' => 'child.father_id' }
+ ]
+ ],
+ { 'mother.person_id' => 'child.mother_id' }
+ ],
+ ]
+ },
+ );
+
+ # Equivalent SQL:
+ # SELECT mother.* FROM person mother
+ # JOIN (
+ # person child
+ # JOIN person father
+ # ON ( father.person_id = child.father_id )
+ # )
+ # ON ( mother.person_id = child.mother_id )
+
+The type of any join can be controlled manually. To search against only people
+with a father in the person table, we could explicitly use C<INNER JOIN>:
+
+ $rs = $schema->resultset('Person')->search(
+ undef,
+ {
+ alias => 'child', # alias columns in accordance with "from"
+ from => [
+ { child => 'person' },
+ [
+ { father => 'person', -join-type => 'inner' },
+ { 'father.id' => 'child.father_id' }
+ ],
+ ]
+ },
+ );
+
+ # Equivalent SQL:
+ # SELECT child.* FROM person child
+ # INNER JOIN person father ON child.father_id = father.id
=head2 page
-For a paged resultset, specifies which page to retrieve. Leave unset
+=over 4
+
+=item Arguments: ($page)
+
+=back
+
+For a paged resultset, specifies which page to retrieve. Leave unset
for an unpaged resultset.
=head2 rows
-For a paged resultset, how many rows per page
+=over 4
+
+=item Arguments: ($rows)
+
+=back
+
+For a paged resultset, specifies how many rows are in each page:
+
+ rows => 10
+
+Can also be used to simulate an SQL C<LIMIT>.
=head2 group_by
-A list of columns to group by (note that 'count' doesn't work on grouped
-resultsets)
+=over 4
+
+=item Arguments: (\@columns)
+
+=back
+
+A arrayref of columns to group by. Can include columns of joined tables.
+
+ group_by => [qw/ column1 column2 ... /]
=head2 distinct
-Set to 1 to group by all columns
+Set to 1 to group by all columns.
+
+=head2 cache
+
+Set to 1 to cache search results. This prevents extra SQL queries if you
+revisit rows in your ResultSet:
+
+ my $resultset = $schema->resultset('Artist')->search( undef, { cache => 1 } );
+
+ while( my $artist = $resultset->next ) {
+ ... do stuff ...
+ }
+
+ $rs->first; # without cache, this would issue a query
+
+By default, searches are not cached.
+
+For more examples of using these attributes, see
+L<DBIx::Class::Manual::Cookbook>.
=cut