=head1 NAME
-DBIX::Class::ResultSet - Responsible for fetching and creating resultset.
+DBIx::Class::ResultSet - Responsible for fetching and creating resultset.
-=head1 SYNOPSIS;
+=head1 SYNOPSIS
-$rs=MyApp::DB::Class->search(registered=>1);
+my $rs = MyApp::DB::Class->search(registered => 1);
+my @rows = MyApp::DB::Class->search(foo => 'bar');
=head1 DESCRIPTION
-The resultset is also known as an iterator.
+The resultset is also known as an iterator. It is responsible for handling
+queries that may return an arbitrary number of rows, e.g. via C<search>
+or a C<has_many> relationship.
=head1 METHODS
-=over 4
+=head2 new($db_class, \%$attrs)
-=item new <db_class> <attrs>
-
-The resultset constructor. Takes a db class and an
-attribute hash (see below for more info on attributes)
+The resultset constructor. Takes a table class and an attribute hash
+(see below for more information on attributes). Does not perform
+any queries -- these are executed as needed by the other methods.
=cut
sub new {
- my ($it_class, $db_class, $attrs) = @_;
+ my ($class, $db_class, $attrs) = @_;
#use Data::Dumper; warn Dumper(@_);
- $it_class = ref $it_class if ref $it_class;
+ $class = ref $class if ref $class;
$attrs = { %{ $attrs || {} } };
my %seen;
$attrs->{cols} ||= [ map { "me.$_" } $db_class->_select_columns ];
$db_class->_relationships->{$pre}->{class}->_select_columns);
}
my $new = {
- class => $db_class,
- cols => $attrs->{cols} || [ $db_class->_select_columns ],
+ source => $db_class,
+ cols => $attrs->{cols},
cond => $attrs->{where},
- from => $attrs->{from} || $db_class->_table_name,
+ from => $attrs->{from},
count => undef,
pager => undef,
attrs => $attrs };
- bless ($new, $it_class);
+ bless ($new, $class);
$new->pager if ($attrs->{page});
return $new;
}
-=item cursor
+=head2 search
+
+ my @obj = $rs->search({ foo => 3 }); # "... WHERE foo = 3"
+ my $new_rs = $rs->search({ foo => 3 });
+
+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"
+
+=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} ] }
+ : $where);
+ $attrs->{where} = $where;
+ }
+
+ my $rs = $self->new($self->{source}, $attrs);
+
+ return (wantarray ? $rs->all : $rs);
+}
+
+=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
+
+=cut
+
+sub search_literal {
+ my ($self, $cond, @vals) = @_;
+ my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {});
+ $attrs->{bind} = [ @{$self->{attrs}{bind}||[]}, @vals ];
+ return $self->search(\$cond, $attrs);
+}
+
+=head2 cursor
-Return a storage driven cursor to the given resultset.
+Returns a storage-driven cursor to the given resultset.
=cut
sub cursor {
my ($self) = @_;
- my ($db_class, $attrs) = @{$self}{qw/class attrs/};
+ my ($source, $attrs) = @{$self}{qw/source attrs/};
if ($attrs->{page}) {
$attrs->{rows} = $self->pager->entries_per_page;
$attrs->{offset} = $self->pager->skipped;
}
return $self->{cursor}
- ||= $db_class->storage->select($self->{from}, $self->{cols},
+ ||= $source->storage->select($self->{from}, $self->{cols},
$attrs->{where},$attrs);
}
-=item slice <first> <last>
+=head2 search_like
+
+Identical to search except defaults to 'LIKE' instead of '=' in condition
+
+=cut
+
+sub search_like {
+ my $class = shift;
+ my $attrs = { };
+ if (@_ > 1 && ref $_[$#_] eq 'HASH') {
+ $attrs = pop(@_);
+ }
+ my $query = ref $_[0] eq "HASH" ? { %{shift()} }: {@_};
+ $query->{$_} = { 'like' => $query->{$_} } for keys %$query;
+ return $class->search($query, { %$attrs });
+}
+
+=head2 slice($first, $last)
-return a number of elements from the given resultset.
+Returns a subset of elements from the resultset.
=cut
sub slice {
my ($self, $min, $max) = @_;
my $attrs = { %{ $self->{attrs} || {} } };
- $self->{class}->throw("Can't slice without where") unless $attrs->{where};
+ $self->{source}->throw("Can't slice without where") unless $attrs->{where};
$attrs->{offset} = $min;
$attrs->{rows} = ($max ? ($max - $min + 1) : 1);
- my $slice = $self->new($self->{class}, $attrs);
+ my $slice = $self->new($self->{source}, $attrs);
return (wantarray ? $slice->all : $slice);
}
-=item next
+=head2 next
-Returns the next element in this resultset.
+Returns the next element in the resultset (undef is there is none).
=cut
@cols = grep { /\(/ or ! /\./ } @cols;
my $new;
unless ($self->{attrs}{prefetch}) {
- $new = $self->{class}->_row_to_object(\@cols, \@row);
+ $new = $self->{source}->_row_to_object(\@cols, \@row);
} else {
my @main = splice(@row, 0, scalar @cols);
- $new = $self->{class}->_row_to_object(\@cols, \@main);
+ $new = $self->{source}->_row_to_object(\@cols, \@main);
PRE: foreach my $pre (@{$self->{attrs}{prefetch}}) {
- my $rel_obj = $self->{class}->_relationships->{$pre};
- my $pre_class = $self->{class}->resolve_class($rel_obj->{class});
+ my $rel_obj = $self->{source}->_relationships->{$pre};
+ my $pre_class = $self->{source}->resolve_class($rel_obj->{class});
my @pre_cols = $pre_class->_select_columns;
my @vals = splice(@row, 0, scalar @pre_cols);
my $fetched = $pre_class->_row_to_object(\@pre_cols, \@vals);
- $self->{class}->throw("No accessor for prefetched $pre")
+ $self->{source}->throw("No accessor for prefetched $pre")
unless defined $rel_obj->{attrs}{accessor};
if ($rel_obj->{attrs}{accessor} eq 'single') {
foreach my $pri ($rel_obj->{class}->primary_columns) {
} elsif ($rel_obj->{attrs}{accessor} eq 'filter') {
$new->{_inflated_column}{$pre} = $fetched;
} else {
- $self->{class}->throw("Don't know how to store prefetched $pre");
+ $self->{source}->throw("Don't know how to store prefetched $pre");
}
}
}
return $new;
}
-=item count
+=head2 count
-Performs an SQL count with the same query as the resultset was built
-with to find the number of elements.
+Performs an SQL C<COUNT> with the same query as the resultset was built
+with to find the number of elements. If passed arguments, does a search
+on the resultset and counts the results of that.
=cut
-
sub count {
- my ($self) = @_;
- my $db_class = $self->{class};
+ my $self = shift;
+ return $self->search(@_)->count if @_ && defined $_[0];
my $attrs = { %{ $self->{attrs} } };
unless ($self->{count}) {
# offset and order by are not needed to count
delete $attrs->{$_} for qw/offset order_by/;
my @cols = 'COUNT(*)';
- $self->{count} = $db_class->storage->select_single($self->{from}, \@cols,
- $self->{cond}, $attrs);
+ $self->{count} = $self->{source}->storage->select_single(
+ $self->{from}, \@cols, $self->{cond}, $attrs);
}
return 0 unless $self->{count};
return $self->{pager}->entries_on_this_page if ($self->{pager});
: $self->{count};
}
-=item all
+=head2 count_literal
-Returns all elements in the resultset. Is called implictly if the search
-method is used in list context.
+Calls search_literal with the passed arguments, then count.
+
+=cut
+
+sub count_literal { shift->search_literal(@_)->count; }
+
+=head2 all
+
+Returns all elements in the resultset. Called implictly if the resultset
+is returned in list context.
=cut
$self->cursor->all;
}
-=item reset
+=head2 reset
-Reset this resultset's cursor, so you can iterate through the elements again.
+Resets the resultset's cursor, so you can iterate through the elements again.
=cut
return $self;
}
-=item first
+=head2 first
-resets the resultset and returns the first element.
+Resets the resultset and returns the first element.
=cut
return $_[0]->reset->next;
}
-=item delete
+=head2 delete
Deletes all elements in the resultset.
*delete_all = \&delete; # Yeah, yeah, yeah ...
-=item pager
+=head2 pager
Returns a L<Data::Page> object for the current resultset. Only makes
sense for queries with page turned on.
return $self->{pager};
}
-=item page <page>
+=head2 page($page_num)
-Returns a new resultset representing a given page.
+Returns a new resultset for the specified page.
=cut
my ($self, $page) = @_;
my $attrs = $self->{attrs};
$attrs->{page} = $page;
- return $self->new($self->{class}, $attrs);
+ return $self->new($self->{source}, $attrs);
}
-=back
-
=head1 Attributes
-The resultset is responsible for handling the various attributes that
-can be passed in with the search functions. Here's an overview of them:
+The resultset takes various attributes that modify its behavior.
+Here's an overview of them:
-=over 4
+=head2 order_by
-=item 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.
-Which column to order the results by.
+=head2 cols
-=item cols
+Which columns should be retrieved.
-Which cols should be retrieved on the first search.
+=head2 join
-=item 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 relations that should be joined for this query. Can also
-contain a hash referece to refer to that relation's relations.
+=head2 prefetch
-=item from
+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.
-This attribute can contain a arrayref of elements. each element can be another
+=head2 from
+
+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.
-*NOTE* Use this on your own risk. This allows you to shoot your foot off!
-
-=item page
+NOTE: Use this on your own risk. This allows you to shoot your foot off!
-Should the resultset be paged? This can also be enabled by using the
-'page' option.
+=head2 page
-=item rows
+For a paged resultset, specifies which page to retrieve. Leave unset
+for an unpaged resultset.
-For paged resultsset, how many rows per page
+=head2 rows
-=item offset
+For a paged resultset, how many rows per page
-For paged resultsset, which page to start on.
-
-=back
+=cut
1;