X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FResultSet.pm;h=22e9129b429cfa3369185d2c4461260e5b1f997e;hb=eaefb953638f736ee8988251bf8cfc8bedad2563;hp=ae6fb3e581381d8f6a46dca85eafff55fff1d21e;hpb=097d32271638f3d6abacb4db0bca841006536857;p=dbsrgits%2FDBIx-Class.git diff --git a/lib/DBIx/Class/ResultSet.pm b/lib/DBIx/Class/ResultSet.pm index ae6fb3e..22e9129 100644 --- a/lib/DBIx/Class/ResultSet.pm +++ b/lib/DBIx/Class/ResultSet.pm @@ -3,10 +3,16 @@ package DBIx::Class::ResultSet; 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 @@ -14,126 +20,240 @@ DBIx::Class::ResultSet - Responsible for fetching and creating resultset. =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 = $schema->resultset('CD')->search(year => 2005); =head1 DESCRIPTION The resultset is also known as an iterator. It is responsible for handling -queries that may return an arbitrary number of rows, e.g. via C +queries that may return an arbitrary number of rows, e.g. via L or a C relationship. +In the examples below, the following table classes are used: + + package MyApp::Schema::Artist; + use base qw/DBIx::Class/; + __PACKAGE__->load_components(qw/Core/); + __PACKAGE__->table('artist'); + __PACKAGE__->add_columns(qw/artistid name/); + __PACKAGE__->set_primary_key('artistid'); + __PACKAGE__->has_many(cds => 'MyApp::Schema::CD'); + 1; + + package MyApp::Schema::CD; + use base qw/DBIx::Class/; + __PACKAGE__->load_components(qw/Core/); + __PACKAGE__->table('cd'); + __PACKAGE__->add_columns(qw/cdid artist title year/); + __PACKAGE__->set_primary_key('cdid'); + __PACKAGE__->belongs_to(artist => 'MyApp::Schema::Artist'); + 1; + =head1 METHODS -=head2 new($source, \%$attrs) +=head2 new + +=over 4 + +=item Arguments: $source, \%$attrs + +=item Return Value: $rs + +=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) and an attribute hash (see +L 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 called in scalar context: + + my $rs = $schema->resultset('CD')->search({ title => '100th Window' }); + +IMPORTANT: If called on an object, proxies to new_result instead so + + my $cd = $schema->resultset('CD')->new({ title => 'Spoon' }); + +will return a CD object, not a ResultSet. =cut sub new { my $class = shift; return $class->new_result(@_) if ref $class; + my ($source, $attrs) = @_; - #use Data::Dumper; warn Dumper($attrs); + weaken $source; $attrs = Storable::dclone($attrs || {}); # { %{ $attrs || {} } }; - my %seen; + #use Data::Dumper; warn Dumper($attrs); my $alias = ($attrs->{alias} ||= 'me'); - if (!$attrs->{select}) { - my @cols = ($attrs->{cols} - ? @{delete $attrs->{cols}} - : $source->result_class->_select_columns); - $attrs->{select} = [ map { m/\./ ? $_ : "${alias}.$_" } @cols ]; + + $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); } - $attrs->{as} ||= [ map { m/^$alias\.(.*)$/ ? $1 : $_ } @{$attrs->{select}} ]; #use Data::Dumper; warn Dumper(@{$attrs}{qw/select as/}); + $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}}, $source->resolve_join($join, $attrs->{alias})); + push(@{$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}}, $source->resolve_join($pre, $attrs->{alias})) - unless $seen{$pre}; - my @pre = - map { "$pre.$_" } - $source->related_source($pre)->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); - return $new; + attrs => $attrs + }, $class; } =head2 search - my @obj = $rs->search({ foo => 3 }); # "... WHERE foo = 3" - my $new_rs = $rs->search({ foo => 3 }); - +=over 4 + +=item Arguments: $cond, \%attrs? + +=item Return Value: $resultset (scalar context), @row_objs (list context) + +=back + + my @cds = $cd_rs->search({ year => 2001 }); # "... WHERE year = 2001" + my $new_rs = $cd_rs->search({ year => 2005 }); + + my $new_rs = $cd_rs->search([ { year => 2005 }, { year => 2004 } ]); + # year = 2005 OR year = 2004 + 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. + + # "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') { - $attrs = { %$attrs, %{ pop(@_) } }; - } - - my $where = (@_ ? ((@_ == 1 || ref $_[0] eq "HASH") ? shift : {@_}) : undef()); - if (defined $where) { - $where = (defined $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 = (ref $self)->new($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 - my @obj = $rs->search_literal($literal_where_cond, @bind); - my $new_rs = $rs->search_literal($literal_where_cond, @bind); +=head2 search_literal + +=over 4 + +=item Arguments: $sql_fragment, @bind_values + +=item Return Value: $resultset (scalar context), @row_objs (list context) + +=back + + my @cds = $cd_rs->search_literal('year = ? AND title = ?', qw/2001 Reload/); + my $newrs = $artist_rs->search_literal('name = ?', 'Metallica'); Pass a literal chunk of SQL to be added to the conditional part of the -resultset +resultset query. =cut - + sub search_literal { my ($self, $cond, @vals) = @_; my $attrs = (ref $vals[$#vals] eq 'HASH' ? { %{ pop(@vals) } } : {}); @@ -141,93 +261,204 @@ sub search_literal { return $self->search(\$cond, $attrs); } -=head2 find(@colvalues), find(\%cols) +=head2 find + +=over 4 + +=item Arguments: @values | \%cols, \%attrs? -Finds a row based on its primary key(s). +=item Return Value: $row_object -=cut +=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 attribute, to search by a specific key or unique +constraint. For example: + + my $cd = $schema->resultset('CD')->find( + { + artist => 'Massive Attack', + title => 'Mezzanine', + }, + { key => 'artist_title' } + ); + +See also L and L. + +=cut sub find { my ($self, @vals) = @_; my $attrs = (@vals > 1 && ref $vals[$#vals] eq 'HASH' ? pop(@vals) : {}); - my @pk = $self->{source}->primary_columns; - #use Data::Dumper; warn Dumper($attrs, @vals, @pk); - $self->{source}->result_class->throw( "Can't find unless primary columns are defined" ) - unless @pk; + + 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 (@pk == @vals) { + $query = { %{$vals[0]} }; + } elsif (@cols == @vals) { $query = {}; - @{$query}{@pk} = @vals; + @{$query}{@cols} = @vals; } else { $query = {@vals}; } + foreach my $key (grep { ! m/\./ } keys %$query) { + $query->{"$self->{attrs}{alias}.$key"} = delete $query->{$key}; + } #warn Dumper($query); - # Useless -> disabled - #$self->{source}->result_class->throw( "Can't find unless all primary keys are specified" ) - # unless (keys %$query >= @pk); # If we check 'em we run afoul of uc/lc - # column names etc. Not sure what to do yet - return $self->search($query)->next; + + 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?); +=over 4 + +=item Arguments: $cond, \%attrs? + +=item Return Value: $new_resultset + +=back + + $new_rs = $cd_rs->search_related('artist', { + name => 'Emo-R-Us', + }); + +Search the specified relationship, optionally specify a condition and +attributes for matching records. See L for more information. =cut sub search_related { - my ($self, $rel, @rest) = @_; - my $rel_obj = $self->{source}->relationship_info($rel); - $self->{source}->result_class->throw( - "No such relationship ${rel} in search_related") - unless $rel_obj; - my $rs = $self->search(undef, { join => $rel }); - return $self->{source}->schema->resultset($rel_obj->{class} - )->search( undef, - { %{$rs->{attrs}}, - alias => $rel, - select => undef(), - as => undef() } - )->search(@rest); + return shift->related_resultset(shift)->search(@_); } =head2 cursor -Returns a storage-driven cursor to the given resultset. +=over 4 + +=item Arguments: none + +=item Return Value: $cursor + +=back + +Returns a storage-driven cursor to the given resultset. See +L for more information. =cut sub cursor { my ($self) = @_; - my ($source, $attrs) = @{$self}{qw/source attrs/}; - $attrs = { %$attrs }; + 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(@_); +=over 4 + +=item Arguments: $cond? + +=item Return Value: $row_object? + +=back + + my $cd = $schema->resultset('CD')->single({ year => 2001 }); + +Inflates the first result without creating a cursor if the resultset has +any records in it; if not returns nothing. Used by find() as an optimisation. + +=cut + +sub single { + my ($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 + +=over 4 + +=item Arguments: $cond, \%attrs? + +=item Return Value: $resultset (scalar context), @row_objs (list context) + +=back + + # WHERE title LIKE '%blue%' + $cd_rs = $rs->search_like({ title => '%blue%'}); + +Perform a search, but use C instead of C<=> as the condition. Note +that this is simply a convenience method. You most likely want to use +L with specific operators. + +For more information, see L. + +=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 -Returns a subset of elements from the resultset. +=item Arguments: $first, $last + +=item Return Value: $resultset (scalar context), @row_objs (list context) + +=back + +Returns a resultset or object list representing a subset of elements from the +resultset slice is called on. Indexes are from 0 - i.e. to get the first +three records, call + + my ($one, $two, $three) = $rs->slice(0, 2); =cut @@ -237,74 +468,229 @@ sub slice { $attrs->{offset} ||= 0; $attrs->{offset} += $min; $attrs->{rows} = ($max ? ($max - $min + 1) : 1); - my $slice = (ref $self)->new($self->{source}, $attrs); + my $slice = (ref $self)->new($self->result_source, $attrs); return (wantarray ? $slice->all : $slice); } -=head2 next +=head2 next + +=over 4 + +=item Arguments: none -Returns the next element in the resultset (undef is there is none). +=item Return Value: $result? + +=back + +Returns the next element in the resultset (C 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}[0]{$2} = shift @row; - } else { - $me{$col} = shift @row; - } - } - my $new = $self->{source}->result_class->inflate_result( - $self->{source}, \%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 + +=over 4 + +=item Arguments: $result_source? + +=item Return Value: $result_source + +=back + +An accessor for the primary ResultSource object from which this ResultSet +is derived. + +=cut + + =head2 count +=over 4 + +=item Arguments: $cond, \%attrs?? + +=item Return Value: $count + +=back + Performs an SQL C 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 with C, L emulates C +using C. Some databases (notably SQLite) do +not support C with multiple columns. If you are using such a +database, you should only use columns from the main table in your C +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 (defined $self->{count}) { - my $attrs = { %{ $self->{attrs} }, - select => { 'count' => '*' }, - as => [ '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/; - - ($self->{count}) = (ref $self)->new($self->{source}, $attrs)->cursor->next; - } - return 0 unless $self->{count}; - my $count = $self->{count}; + 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} && $self->{attrs}{rows} < $count); + $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; + } + + $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. +=over 4 + +=item Arguments: $sql_fragment, @bind_values + +=item Return Value: $count + +=back + +Counts the results in a literal query. Equivalent to calling L +with the passed arguments, then L. =cut @@ -312,32 +698,79 @@ sub count_literal { shift->search_literal(@_)->count; } =head2 all -Returns all elements in the resultset. Called implictly if the resultset +=over 4 + +=item Arguments: none + +=item Return Value: @objects + +=back + +Returns all elements in the resultset. Called implicitly if the resultset is returned in list context. =cut sub all { my ($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 +=over 4 + +=item Arguments: none + +=item Return Value: $self + +=back + Resets the resultset's cursor, so you can iterate through the elements again. =cut sub reset { my ($self) = @_; + $self->{all_cache_position} = 0; $self->cursor->reset; return $self; } =head2 first -Resets the resultset and returns the first element. +=over 4 + +=item Arguments: none + +=item Return Value: $object? + +=back + +Resets the resultset and returns an object for the first result (if the +resultset contains anything). =cut @@ -345,29 +778,50 @@ sub first { return $_[0]->reset->next; } -=head2 update(\%values) +=head2 update + +=over 4 -Sets the specified columns in the resultset to the supplied values +=item Arguments: \%values + +=item Return Value: $storage_rv + +=back + +Sets the specified columns in the resultset to the supplied values in a +single query. Return value will be true if the update succeeded or false +if no records were updated; exact type of success value is storage-dependent. =cut sub update { my ($self, $values) = @_; - die "Values for update must be a hash" unless ref $values eq 'HASH'; - return $self->{source}->storage->update( - $self->{source}->from, $values, $self->{cond}); + $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, $self->{cond} + ); } -=head2 update_all(\%values) +=head2 update_all + +=over 4 + +=item Arguments: \%values -Fetches all objects and updates them one at a time. ->update_all will run -cascade triggers, ->update will not. +=item Return Value: 1 + +=back + +Fetches all objects and updates them one at a time. Note that C +will run cascade triggers while L will not. =cut sub update_all { my ($self, $values) = @_; - die "Values for update must be a hash" unless ref $values eq 'HASH'; + $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; } @@ -376,20 +830,75 @@ sub update_all { =head2 delete -Deletes the contents of the resultset from its result source. +=over 4 + +=item Arguments: none + +=item Return Value: 1 + +=back + +Deletes the contents of the resultset from its result source. Note that this +will not run cascade triggers. See L if you need triggers to run. =cut sub delete { my ($self) = @_; - $self->{source}->storage->delete($self->{source}->from, $self->{cond}); + 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; } =head2 delete_all -Fetches all objects and deletes them one at a time. ->delete_all will run -cascade triggers, ->delete will not. +=over 4 + +=item Arguments: none + +=item Return Value: 1 + +=back + +Fetches all objects and deletes them one at a time. Note that C +will run cascade triggers while L will not. =cut @@ -401,24 +910,42 @@ sub delete_all { =head2 pager -Returns a L object for the current resultset. Only makes -sense for queries with page turned on. +=over 4 + +=item Arguments: none + +=item Return Value: $pager + +=back + +Return Value a L object for the current resultset. Only makes +sense for queries with a C attribute. =cut sub pager { my ($self) = @_; my $attrs = $self->{attrs}; - die "Can't create pager for non-paged rs" unless $self->{page}; + $self->throw_exception("Can't create pager for non-paged rs") + unless $self->{page}; $attrs->{rows} ||= 10; - $self->count; return $self->{pager} ||= Data::Page->new( - $self->{count}, $attrs->{rows}, $self->{page}); + $self->_count, $attrs->{rows}, $self->{page}); } -=head2 page($page_num) +=head2 page + +=over 4 + +=item Arguments: $page_number -Returns a new resultset for the specified page. +=item Return Value: $rs + +=back + +Returns a resultset for the $page_number page of the resultset on which page +is called, where each page contains a number of rows equal to the 'rows' +attribute set on the resultset, or 10 by default =cut @@ -426,129 +953,660 @@ sub page { my ($self, $page) = @_; my $attrs = { %{$self->{attrs}} }; $attrs->{page} = $page; - return (ref $self)->new($self->{source}, $attrs); + return (ref $self)->new($self->result_source, $attrs); } -=head2 new_result(\%vals) +=head2 new_result + +=over 4 -Creates a result in the resultset's result class +=item Arguments: \%vals + +=item Return Value: $object + +=back + +Creates an object in the resultset's result class and returns it. =cut sub new_result { my ($self, $values) = @_; - $self->{source}->result_class->throw( "new_result needs a hash" ) + $self->throw_exception( "new_result needs a hash" ) unless (ref $values eq 'HASH'); - $self->{source}->result_class->throw( "Can't abstract implicit construct, condition not a hash" ) - if ($self->{cond} && !(ref $self->{cond} 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 ($key =~ m/^(?:$alias\.)?([^\.]+)$/); + $new{$1} = $self->{cond}{$key} if ($key =~ m/^(?:\Q${alias}.\E)?([^.]+)$/); } - my $obj = $self->{source}->result_class->new(\%new); - $obj->result_source($self->{source}) if $obj->can('result_source'); - $obj; + my $obj = $self->result_class->new(\%new); + $obj->result_source($self->result_source) if $obj->can('result_source'); + return $obj; } -=head2 create(\%vals) +=head2 create + +=over 4 + +=item Arguments: \%vals + +=item Return Value: $object -Inserts a record into the resultset and returns the object +=back -Effectively a shortcut for ->new_result(\%vals)->insert +Inserts a record into the resultset and returns the object representing it. + +Effectively a shortcut for C<< ->new_result(\%vals)->insert >>. =cut sub create { my ($self, $attrs) = @_; - $self->{source}->result_class->throw( "create needs a hashref" ) unless ref $attrs eq 'HASH'; + $self->throw_exception( "create needs a hashref" ) + unless ref $attrs eq 'HASH'; return $self->new_result($attrs)->insert; } -=head2 find_or_create(\%vals) +=head2 find_or_create + +=over 4 + +=item Arguments: \%vals, \%attrs? + +=item Return Value: $object + +=back + + $class->find_or_create({ key => $val, ... }); + +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 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 and L. - $class->find_or_create({ key => $val, ... }); - -Searches for a record matching the search condition; if it doesn't find one, -creates one and returns that instead. - =cut sub find_or_create { my $self = shift; - my $hash = ref $_[0] eq "HASH" ? shift: {@_}; - my $exists = $self->find($hash); - return defined($exists) ? $exists : $self->create($hash); + 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 + +=over 4 + +=item Arguments: \%col_values, { key => $unique_constraint }? + +=item Return Value: $object + +=back + + $class->update_or_create({ col => $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 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 is specified, it searches on all unique constraints defined on the +source, including the primary key. + +If the C is specified as C, search only on the primary key. + +See also L and L. + +=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 + +=over 4 + +=item Arguments: none + +=item Return Value: \@cache_objects? + +=back + +Gets the contents of the cache for the resultset if the cache is set + +=cut + +sub get_cache { + shift->{all_cache} || []; +} + +=head2 set_cache + +=over 4 + +=item Arguments: \@cache_objects + +=item Return Value: \@cache_objects + +=back + +Sets the contents of the cache for the resultset. Expects an arrayref +of objects of the same class as those produced by the resultset. Note that +if the cache is set the resultset will return the cached objects rather +than re-querying the database even if the cache attr is not set. + +=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 + +=over 4 + +=item Arguments: none + +=item Return Value: [] + +=back + +Clears the cache for the resultset. + +=cut + +sub clear_cache { + shift->set_cache([]); +} + +=head2 related_resultset + +=over 4 + +=item Arguments: $relationship_name + +=item Return Value: $resultset + +=back + +Returns a related resultset for the supplied relationship name. + + $artist_rs = $schema->resultset('CD')->related_resultset('Artist'); + +=cut + +sub related_resultset { + my ( $self, $rel ) = @_; + $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 } + ); + }; } +=head2 throw_exception + +See L for details. + +=cut + +sub throw_exception { + my $self=shift; + $self->result_source->schema->throw_exception(@_); +} + +# XXX: FIXME: Attributes docs need clearing up + =head1 ATTRIBUTES -The resultset takes various attributes that modify its behavior. -Here's an overview of them: +The resultset takes various attributes that modify its behavior. Here's an +overview of them: =head2 order_by +=over 4 + +=item Value: ($order_by | \@order_by) + +=back + Which column(s) to order the results by. This is currently passed -through directly to SQL, so you can give e.g. C for a -descending order. +through directly to SQL, so you can give e.g. C for a +descending order on the column `year'. + +=head2 columns + +=over 4 + +=item Value: \@columns + +=back + +Shortcut to request a particular set of columns to be retrieved. Adds +C onto the start of any column without a C<.> in it and sets C as normal. (You may also +use the C attribute, as in earlier versions of DBIC.) + +=head2 include_columns + +=over 4 + +=item Value: \@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 -=head2 cols (arrayref) +=item Value: \@select_columns -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 +=back -=head2 select (arrayref) +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: -Indicates which columns should be selected from the storage + $rs = $schema->resultset('Employee')->search(undef, { + select => [ + 'name', + { count => 'employeeid' }, + { sum => 'salary' } + ] + }); -=head2 as (arrayref) +When you use function/stored procedure names and do not supply an C +attribute, the column names returned are storage-dependent. E.g. MySQL would +return a column named C in the above example. -Indicates column names for object inflation +=head2 as + +=over 4 + +=item Value: \@inflation_names + +=back + +Indicates column names for object inflation. This is used in conjunction with +C 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, 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 instead: + + my $employee_count = $employee->get_column('employee_count'); + +You can create your own accessors if required - see +L for details. =head2 join -Contains a list of relationships that should be joined for this query. Can also -contain a hash reference to refer to that relation's relations. So, if one column -in your class C foo and another C bar, you can do -C<< join => [qw/ foo bar /] >> to join both (and e.g. use them for C). -If a foo contains many margles and you want to join those too, you can do -C<< join => { foo => 'margle' } >>. If you want to fetch the columns from the -related table as well, see C below. +=over 4 + +=item Value: ($rel_name | \@rel_names | \%rel_names) + +=back + +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 _2 (and +similarly for a third time). For e.g. + + my $rs = $schema->resultset('Artist')->search({ + 'cds.title' => 'Down to Earth', + 'cds_2.title' => 'Popular', + }, { + join => [ qw/cds cds/ ], + }); + +will return a set of all artists that have both a cd with title 'Down +to Earth' and a cd with title 'Popular'. + +If you want to fetch related objects from other tables as well, see C +below. =head2 prefetch -Contains a list of relationships that should be fetched along with the main -query (when they are accessed afterwards they will have already been -"prefetched"). This is useful for when you know you will need the related -object(s), because it saves a query. Currently limited to prefetching -one relationship deep, so unlike C, prefetch must be an arrayref. +=over 4 -=head2 from +=item Value: ($rel_name | \@rel_names | \%rel_names) -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 has no need to go back to the database when we access the +C or C relationships, which saves us two SQL statements in this +case. + +Simple prefetches will be joined automatically, so there is no need +for a C 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 can be used with the following relationship types: C, +C (or if you're using C, any relationship declared +with an accessor type of 'single' or 'filter'). + +=head2 from + +=over 4 + +=item Value: \@from_clause + +=back + +The C attribute gives you manual control over the C clause of SQL +statements generated by L, allowing you to express custom C +clauses. + +NOTE: Use this on your own risk. This allows you to shoot off your foot! +C will usually do what you need and it is strongly recommended that you +avoid using C unless you cannot achieve the desired result using C. + +In simple terms, C works as follows: + + [ + { => , -join-type => 'inner|left|right' } + [] # nested JOIN (optional) + { => } + ] + + JOIN +
+ [JOIN ...] + ON = + +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 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: + + $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 -for an unpaged resultset. +=over 4 + +=item Value: $page + +=back + +Makes the resultset paged and specifies the page to retrieve. Effectively +identical to creating a non-pages resultset and then calling ->page($page) +on it. =head2 rows -For a paged resultset, how many rows per page +=over 4 + +=item Value: $rows + +=back + +Specifes the maximum number of rows for direct retrieval or the number of +rows per page if the page attribute or method is used. =head2 group_by -A list of columns to group by (note that 'count' doesn't work on grouped -resultsets) +=over 4 + +=item Value: \@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 +=over 4 + +=item Value: (0 | 1) + +=back + +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. =cut