X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FResultSet.pm;h=1610eb11823ce43274bfa90a580b68964bce0119;hb=ed899df367fc90a6b30f1e17d0ea4e2bc2e094f6;hp=9367b3cb38f317ecfb025e8519329d86037f03fb;hpb=22f4bed4c9a054c28a88337df9e1df815288661e;p=dbsrgits%2FDBIx-Class.git diff --git a/lib/DBIx/Class/ResultSet.pm b/lib/DBIx/Class/ResultSet.pm index 9367b3c..1610eb1 100644 --- a/lib/DBIx/Class/ResultSet.pm +++ b/lib/DBIx/Class/ResultSet.pm @@ -3,17 +3,19 @@ package DBIx::Class::ResultSet; use strict; use warnings; use overload - '0+' => \&count, - 'bool' => sub { 1; }, + '0+' => "count", + 'bool' => "_bool", fallback => 1; use Carp::Clan qw/^DBIx::Class/; use Data::Page; use Storable; use DBIx::Class::ResultSetColumn; use DBIx::Class::ResultSourceHandle; +use List::Util (); +use Scalar::Util (); use base qw/DBIx::Class/; -__PACKAGE__->mk_group_accessors('simple' => qw/result_class _source_handle/); +__PACKAGE__->mk_group_accessors('simple' => qw/_result_class _source_handle/); =head1 NAME @@ -21,8 +23,8 @@ DBIx::Class::ResultSet - Responsible for fetching and creating resultset. =head1 SYNOPSIS - my $rs = $schema->resultset('User')->search(registered => 1); - my @rows = $schema->resultset('CD')->search(year => 2005); + my $rs = $schema->resultset('User')->search({ registered => 1 }); + my @rows = $schema->resultset('CD')->search({ year => 2005 })->all(); =head1 DESCRIPTION @@ -50,6 +52,13 @@ In the examples below, the following table classes are used: __PACKAGE__->belongs_to(artist => 'MyApp::Schema::Artist'); 1; +=head1 OVERLOADING + +If a resultset is used in a numeric context it returns the L. +However, if it is used in a booleand context it is always true. So if +you want to check if a resultset has any results use C. +C will always be true. + =head1 METHODS =head2 new @@ -91,15 +100,14 @@ sub new { if ($attrs->{page}) { $attrs->{rows} ||= 10; - $attrs->{offset} ||= 0; - $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1)); } $attrs->{alias} ||= 'me'; + # Creation of {} and bless separated to mitigate RH perl bug + # see https://bugzilla.redhat.com/show_bug.cgi?id=196836 my $self = { - result_source => $source, - result_class => $attrs->{result_class} || $source->result_class, + _source_handle => $source, cond => $attrs->{where}, count => undef, pager => undef, @@ -108,6 +116,10 @@ sub new { bless $self, $class; + $self->result_class( + $attrs->{result_class} || $source->resolve->result_class + ); + return $self; } @@ -140,6 +152,8 @@ L. For more examples of using this function, see L. For a complete documentation for the first argument, see L. +For more help on using joins with search, see L. + =cut sub search { @@ -166,22 +180,30 @@ always return a resultset, even in list context. sub search_rs { my $self = shift; - my $rows; - - unless (@_) { # no search, effectively just a clone - $rows = $self->get_cache; - } - my $attrs = {}; $attrs = pop(@_) if @_ > 1 and ref $_[$#_] eq 'HASH'; my $our_attrs = { %{$self->{attrs}} }; my $having = delete $our_attrs->{having}; my $where = delete $our_attrs->{where}; + my $rows; + + my %safe = (alias => 1, cache => 1); + + unless ( + (@_ && defined($_[0])) # @_ == () or (undef) + || + (keys %$attrs # empty attrs or only 'safe' attrs + && List::Util::first { !$safe{$_} } keys %$attrs) + ) { + # no search, effectively just a clone + $rows = $self->get_cache; + } + my $new_attrs = { %{$our_attrs}, %{$attrs} }; # merge new attrs into inherited - foreach my $key (qw/join prefetch/) { + foreach my $key (qw/join prefetch +select +as/) { next unless exists $attrs->{$key}; $new_attrs->{$key} = $self->_merge_attr($our_attrs->{$key}, $attrs->{$key}); } @@ -266,6 +288,13 @@ sub search_rs { Pass a literal chunk of SQL to be added to the conditional part of the resultset query. +CAVEAT: C is provided for Class::DBI compatibility and should +only be used in that context. There are known problems using C +in chained queries; it can result in bind values in the wrong order. See +L and +L for searching techniques that do not +require C. + =cut sub search_literal { @@ -281,7 +310,7 @@ sub search_literal { =item Arguments: @values | \%cols, \%attrs? -=item Return Value: $row_object +=item Return Value: $row_object | undef =back @@ -310,11 +339,18 @@ Additionally, you can specify the columns explicitly by name: If the C is specified as C, it searches only on the primary key. If no C is specified, it searches on all unique constraints defined on the -source, including the primary key. +source for which column data is provided, including the primary key. If your table does not have a primary key, you B provide a value for the C attribute matching one of the unique constraints on the source. +In addition to C, L recognizes and applies standard +L in the same way as L does. + +Note: If your query does not return only one row, a warning is generated: + + Query returned more than one row + See also L and L. For information on how to declare unique constraints, see L. @@ -350,11 +386,13 @@ sub find { my (%related, $info); - foreach my $key (keys %$input_query) { + KEY: foreach my $key (keys %$input_query) { if (ref($input_query->{$key}) && ($info = $self->result_source->relationship_info($key))) { + my $val = delete $input_query->{$key}; + next KEY if (ref($val) eq 'ARRAY'); # has_many for multi_create my $rel_q = $self->result_source->resolve_condition( - $info->{cond}, delete $input_query->{$key}, $key + $info->{cond}, $val, $key ); die "Can't handle OR join condition in find" if ref($rel_q) eq 'ARRAY'; @related{keys %$rel_q} = values %$rel_q; @@ -364,25 +402,46 @@ sub find { @{$input_query}{@keys} = values %related; } - my @unique_queries = $self->_unique_queries($input_query, $attrs); # Build the final query: Default to the disjunction of the unique queries, # but allow the input query in case the ResultSet defines the query or the # user is abusing find my $alias = exists $attrs->{alias} ? $attrs->{alias} : $self->{attrs}{alias}; - my $query = @unique_queries - ? [ map { $self->_add_alias($_, $alias) } @unique_queries ] - : $self->_add_alias($input_query, $alias); + my $query; + if (exists $attrs->{key}) { + my @unique_cols = $self->result_source->unique_constraint_columns($attrs->{key}); + my $unique_query = $self->_build_unique_query($input_query, \@unique_cols); + $query = $self->_add_alias($unique_query, $alias); + } + else { + my @unique_queries = $self->_unique_queries($input_query, $attrs); + $query = @unique_queries + ? [ map { $self->_add_alias($_, $alias) } @unique_queries ] + : $self->_add_alias($input_query, $alias); + } # Run the query if (keys %$attrs) { my $rs = $self->search($query, $attrs); - return keys %{$rs->_resolved_attrs->{collapse}} ? $rs->next : $rs->single; + if (keys %{$rs->_resolved_attrs->{collapse}}) { + my $row = $rs->next; + carp "Query returned more than one row" if $rs->next; + return $row; + } + else { + return $rs->single; + } } else { - return keys %{$self->_resolved_attrs->{collapse}} - ? $self->search($query)->next - : $self->single($query); + if (keys %{$self->_resolved_attrs->{collapse}}) { + my $rs = $self->search($query); + my $row = $rs->next; + carp "Query returned more than one row" if $rs->next; + return $row; + } + else { + return $self->single($query); + } } } @@ -472,6 +531,17 @@ sub search_related { return shift->related_resultset(shift)->search(@_); } +=head2 search_related_rs + +This method works exactly the same as search_related, except that +it guarantees a restultset, even in list context. + +=cut + +sub search_related_rs { + return shift->related_resultset(shift)->search_rs(@_); +} + =head2 cursor =over 4 @@ -509,16 +579,38 @@ sub cursor { 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 L as an optimisation. +any records in it; if not returns nothing. Used by L as a lean version of +L. + +While this method can take an optional search condition (just like L) +being a fast-code-path it does not recognize search attributes. If you need to +add extra joins or similar, call L and then chain-call L on the +L returned. + +=over -Can optionally take an additional condition *only* - this is a fast-code-path -method; if you need to add extra joins or similar call ->search and then -->single without a condition on the $rs returned from that. +=item B + +As of 0.08100, this method enforces the assumption that the preceeding +query returns only one row. If more than one row is returned, you will receive +a warning: + + Query returned more than one row + +In this case, you should be using L or L instead, or if you really +know what you are doing, use the L attribute to explicitly limit the size +of the resultset. + +=back =cut sub single { my ($self, $where) = @_; + if(@_ > 2) { + $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()'); + } + my $attrs = { %{$self->_resolved_attrs} }; if ($where) { if (defined $attrs->{where}) { @@ -543,7 +635,7 @@ sub single { $attrs->{where}, $attrs ); - return (@data ? ($self->_construct_object(@data))[0] : ()); + return (@data ? ($self->_construct_object(@data))[0] : undef); } # _is_unique_query @@ -649,8 +741,8 @@ sub get_column { $cd_rs = $rs->search_like({ title => '%blue%'}); Performs a search, but uses 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. +that this is simply a convenience method retained for ex Class::DBI users. +You most likely want to use L with specific operators. For more information, see L. @@ -738,7 +830,7 @@ sub next { ? @{delete $self->{stashed_row}} : $self->cursor->next ); - return unless (@row); + return undef unless (@row); my ($row, @more) = $self->_construct_object(@row); $self->{stashed_objects} = \@more if @more; return $row; @@ -782,7 +874,8 @@ sub _collapse_result { if (keys %collapse) { my %pri = map { ($_ => 1) } $self->result_source->primary_columns; foreach my $i (0 .. $#construct_as) { - if (delete $pri{$construct_as[$i]}) { + next if defined($construct_as[$i][0]); # only self table + if (delete $pri{$construct_as[$i][1]}) { push(@pri_index, $i); } last unless keys %pri; # short circuit (Johnny Five Is Alive!) @@ -793,14 +886,18 @@ sub _collapse_result { my %pri_vals = map { ($_ => $copy[$_]) } @pri_index; - my %const; + my @const_rows; do { # no need to check anything at the front, we always want the first row + + my %const; foreach my $this_as (@construct_as) { $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy); } + push(@const_rows, \%const); + } until ( # no pri_index => no collapse => drop straight out !@pri_index or @@ -821,20 +918,48 @@ sub _collapse_result { } ); - # THIS BIT STILL NEEDS TO DO THE COLLAPSE - my $alias = $self->{attrs}{alias}; - my $info = [ {}, {} ]; - foreach my $key (keys %const) { - if (length $key && $key ne $alias) { - my $target = $info; - my @parts = split(/\./, $key); - foreach my $p (@parts) { - $target = $target->[1]->{$p} ||= []; + my $info = []; + + my %collapse_pos; + + my @const_keys; + + foreach my $const (@const_rows) { + scalar @const_keys or do { + @const_keys = sort { length($a) <=> length($b) } keys %$const; + }; + foreach my $key (@const_keys) { + if (length $key) { + my $target = $info; + my @parts = split(/\./, $key); + my $cur = ''; + my $data = $const->{$key}; + foreach my $p (@parts) { + $target = $target->[1]->{$p} ||= []; + $cur .= ".${p}"; + if ($cur eq ".${key}" && (my @ckey = @{$collapse{$cur}||[]})) { + # collapsing at this point and on final part + my $pos = $collapse_pos{$cur}; + CK: foreach my $ck (@ckey) { + if (!defined $pos->{$ck} || $pos->{$ck} ne $data->{$ck}) { + $collapse_pos{$cur} = $data; + delete @collapse_pos{ # clear all positioning for sub-entries + grep { m/^\Q${cur}.\E/ } keys %collapse_pos + }; + push(@$target, []); + last CK; + } + } + } + if (exists $collapse{$cur}) { + $target = $target->[-1]; + } + } + $target->[0] = $data; + } else { + $info->[0] = $const->{$key}; } - $target->[0] = $const{$key}; - } else { - $info->[0] = $const{$key}; } } @@ -870,6 +995,14 @@ L<"table"|DBIx::Class::Manual::Glossary/"ResultSource"> class. =cut +sub result_class { + my ($self, $result_class) = @_; + if ($result_class) { + $self->ensure_class_loaded($result_class); + $self->_result_class($result_class); + } + $self->_result_class; +} =head2 count @@ -885,7 +1018,7 @@ 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 +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 @@ -900,9 +1033,12 @@ sub count { my $count = $self->_count; return 0 unless $count; - $count -= $self->{attrs}{offset} if $self->{attrs}{offset}; + # need to take offset from resolved attrs + + $count -= $self->{_attrs}{offset} if $self->{_attrs}{offset}; $count = $self->{attrs}{rows} if $self->{attrs}{rows} and $self->{attrs}{rows} < $count; + $count = 0 if ($count < 0); return $count; } @@ -935,11 +1071,15 @@ sub _count { # Separated out so pager can get the full 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 $tmp_rs = (ref $self)->new($self->_source_handle, $attrs); + my $tmp_rs = (ref $self)->new($self->result_source, $attrs); my ($count) = $tmp_rs->cursor->next; return $count; } +sub _bool { + return 1; +} + =head2 count_literal =over 4 @@ -973,7 +1113,11 @@ is returned in list context. =cut sub all { - my ($self) = @_; + my $self = shift; + if(@_) { + $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()"); + } + return @{ $self->get_cache } if $self->get_cache; my @obj; @@ -1171,11 +1315,26 @@ Deletes the contents of the resultset from its result source. Note that this will not run DBIC cascade triggers. See L if you need triggers to run. See also L. +delete may not generate correct SQL for a query with joins or a resultset +chained from a related resultset. In this case it will generate a warning:- + + WARNING! Currently $rs->delete() does not generate proper SQL on + joined resultsets, and may delete rows well outside of the contents + of $rs. Use at your own risk + +In these cases you may find that delete_all is more appropriate, or you +need to respecify your query in a way that can be expressed without a join. + =cut sub delete { my ($self) = @_; - + $self->throw_exception("Delete should not be passed any arguments") + if $_[1]; + carp( 'WARNING! Currently $rs->delete() does not generate proper SQL' + . ' on joined resultsets, and may delete rows well outside of the' + . ' contents of $rs. Use at your own risk' ) + if ( $self->{attrs}{seen_join} ); my $cond = $self->_cond_for_update_delete; $self->result_source->storage->delete($self->result_source, $cond); @@ -1203,6 +1362,178 @@ sub delete_all { return 1; } +=head2 populate + +=over 4 + +=item Arguments: \@data; + +=back + +Accepts either an arrayref of hashrefs or alternatively an arrayref of arrayrefs. +For the arrayref of hashrefs style each hashref should be a structure suitable +forsubmitting to a $resultset->create(...) method. + +In void context, C in L is used +to insert the data, as this is a faster method. + +Otherwise, each set of data is inserted into the database using +L, and a arrayref of the resulting row +objects is returned. + +Example: Assuming an Artist Class that has many CDs Classes relating: + + my $Artist_rs = $schema->resultset("Artist"); + + ## Void Context Example + $Artist_rs->populate([ + { artistid => 4, name => 'Manufactured Crap', cds => [ + { title => 'My First CD', year => 2006 }, + { title => 'Yet More Tweeny-Pop crap', year => 2007 }, + ], + }, + { artistid => 5, name => 'Angsty-Whiny Girl', cds => [ + { title => 'My parents sold me to a record company' ,year => 2005 }, + { title => 'Why Am I So Ugly?', year => 2006 }, + { title => 'I Got Surgery and am now Popular', year => 2007 } + ], + }, + ]); + + ## Array Context Example + my ($ArtistOne, $ArtistTwo, $ArtistThree) = $Artist_rs->populate([ + { name => "Artist One"}, + { name => "Artist Two"}, + { name => "Artist Three", cds=> [ + { title => "First CD", year => 2007}, + { title => "Second CD", year => 2008}, + ]} + ]); + + print $ArtistOne->name; ## response is 'Artist One' + print $ArtistThree->cds->count ## reponse is '2' + +For the arrayref of arrayrefs style, the first element should be a list of the +fieldsnames to which the remaining elements are rows being inserted. For +example: + + $Arstist_rs->populate([ + [qw/artistid name/], + [100, 'A Formally Unknown Singer'], + [101, 'A singer that jumped the shark two albums ago'], + [102, 'An actually cool singer.'], + ]); + +Please note an important effect on your data when choosing between void and +wantarray context. Since void context goes straight to C in +L this will skip any component that is overriding +c. So if you are using something like L to +create primary keys for you, you will find that your PKs are empty. In this +case you will have to use the wantarray context in order to create those +values. + +=cut + +sub populate { + my $self = shift @_; + my $data = ref $_[0][0] eq 'HASH' + ? $_[0] : ref $_[0][0] eq 'ARRAY' ? $self->_normalize_populate_args($_[0]) : + $self->throw_exception('Populate expects an arrayref of hashes or arrayref of arrayrefs'); + + if(defined wantarray) { + my @created; + foreach my $item (@$data) { + push(@created, $self->create($item)); + } + return @created; + } else { + my ($first, @rest) = @$data; + + my @names = grep {!ref $first->{$_}} keys %$first; + my @rels = grep { $self->result_source->has_relationship($_) } keys %$first; + my @pks = $self->result_source->primary_columns; + + ## do the belongs_to relationships + foreach my $index (0..$#$data) { + if( grep { !defined $data->[$index]->{$_} } @pks ) { + my @ret = $self->populate($data); + return; + } + + foreach my $rel (@rels) { + next unless $data->[$index]->{$rel} && ref $data->[$index]->{$rel} eq "HASH"; + my $result = $self->related_resultset($rel)->create($data->[$index]->{$rel}); + my ($reverse) = keys %{$self->result_source->reverse_relationship_info($rel)}; + my $related = $result->result_source->resolve_condition( + $result->result_source->relationship_info($reverse)->{cond}, + $self, + $result, + ); + + delete $data->[$index]->{$rel}; + $data->[$index] = {%{$data->[$index]}, %$related}; + + push @names, keys %$related if $index == 0; + } + } + + ## do bulk insert on current row + my @values = map { [ @$_{@names} ] } @$data; + + $self->result_source->storage->insert_bulk( + $self->result_source, + \@names, + \@values, + ); + + ## do the has_many relationships + foreach my $item (@$data) { + + foreach my $rel (@rels) { + next unless $item->{$rel} && ref $item->{$rel} eq "ARRAY"; + + my $parent = $self->find(map {{$_=>$item->{$_}} } @pks) + || $self->throw_exception('Cannot find the relating object.'); + + my $child = $parent->$rel; + + my $related = $child->result_source->resolve_condition( + $parent->result_source->relationship_info($rel)->{cond}, + $child, + $parent, + ); + + my @rows_to_add = ref $item->{$rel} eq 'ARRAY' ? @{$item->{$rel}} : ($item->{$rel}); + my @populate = map { {%$_, %$related} } @rows_to_add; + + $child->populate( \@populate ); + } + } + } +} + +=head2 _normalize_populate_args ($args) + +Private method used by L to normalize its incoming arguments. Factored +out in case you want to subclass and accept new argument structures to the +L method. + +=cut + +sub _normalize_populate_args { + my ($self, $data) = @_; + my @names = @{shift(@$data)}; + my @results_to_create; + foreach my $datum (@$data) { + my %result_to_create; + foreach my $index (0..$#names) { + $result_to_create{$names[$index]} = $$datum[$index]; + } + push @results_to_create, \%result_to_create; + } + return \@results_to_create; +} + =head2 pager =over 4 @@ -1246,7 +1577,7 @@ attribute set on the resultset (10 by default). sub page { my ($self, $page) = @_; - return (ref $self)->new($self->_source_handle, { %{$self->{attrs}}, page => $page }); + return (ref $self)->new($self->result_source, { %{$self->{attrs}}, page => $page }); } =head2 new_result @@ -1255,11 +1586,16 @@ sub page { =item Arguments: \%vals -=item Return Value: $object +=item Return Value: $rowobject =back -Creates an object in the resultset's result class and returns it. +Creates a new row object in the resultset's result class and returns +it. The row is not inserted into the database at this point, call +L to do that. Calling L +will tell you whether the row object has been inserted or not. + +Passes the hashref of input on to L. =cut @@ -1267,21 +1603,62 @@ sub new_result { my ($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; my $alias = $self->{attrs}{alias}; - my $collapsed_cond = $self->{cond} ? $self->_collapse_cond($self->{cond}) : {}; - my %new = ( + + if ( + defined $self->{cond} + && $self->{cond} eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION + ) { + %new = %{$self->{attrs}{related_objects}}; + } else { + $self->throw_exception( + "Can't abstract implicit construct, condition not a hash" + ) if ($self->{cond} && !(ref $self->{cond} eq 'HASH')); + + my $collapsed_cond = ( + $self->{cond} + ? $self->_collapse_cond($self->{cond}) + : {} + ); + + # precendence must be given to passed values over values inherited from + # the cond, so the order here is important. + my %implied = %{$self->_remove_alias($collapsed_cond, $alias)}; + while( my($col,$value) = each %implied ){ + if(ref($value) eq 'HASH' && keys(%$value) && (keys %$value)[0] eq '='){ + $new{$col} = $value->{'='}; + next; + } + $new{$col} = $value if $self->_is_deterministic_value($value); + } + } + + %new = ( + %new, %{ $self->_remove_alias($values, $alias) }, - %{ $self->_remove_alias($collapsed_cond, $alias) }, - -source_handle => $self->_source_handle + -source_handle => $self->_source_handle, + -result_source => $self->result_source, # DO NOT REMOVE THIS, REQUIRED ); return $self->result_class->new(\%new); } +# _is_deterministic_value +# +# Make an effor to strip non-deterministic values from the condition, +# to make sure new_result chokes less + +sub _is_deterministic_value { + my $self = shift; + my $value = shift; + my $ref_type = ref $value; + return 1 if $ref_type eq '' || $ref_type eq 'SCALAR'; + return 1 if Scalar::Util::blessed($value); + return 0; +} + # _collapse_cond # # Recursively collapse the condition. @@ -1346,16 +1723,33 @@ sub _remove_alias { =item Arguments: \%vals, \%attrs? -=item Return Value: $object +=item Return Value: $rowobject =back -Find an existing record from this resultset. If none exists, instantiate a new -result object and return it. The object will not be saved into your storage + my $artist = $schema->resultset('Artist')->find_or_new( + { artist => 'fred' }, { key => 'artists' }); + + $cd->cd_to_producer->find_or_new({ producer => $producer }, + { key => 'primary }); + +Find an existing record from this resultset, based on its primary +key, or a unique constraint. If none exists, instantiate a new result +object and return it. The object will not be saved into your storage until you call L on it. +You most likely want this method when looking for existing rows using +a unique constraint that is not the primary key, or looking for +related rows. + If you want objects to be saved immediately, use L instead. +B: C is probably not what you want when creating a +new row in a table that uses primary keys supplied by the +database. Passing in a primary key column with a value of I +will cause L to attempt to search for a row with a value of +I. + =cut sub find_or_new { @@ -1372,14 +1766,63 @@ sub find_or_new { =item Arguments: \%vals -=item Return Value: $object +=item Return Value: a L $object =back -Inserts a record into the resultset and returns the object representing it. +Attempt to create a single new row or a row with multiple related rows +in the table represented by the resultset (and related tables). This +will not check for duplicate rows before inserting, use +L to do that. + +To create one row for this resultset, pass a hashref of key/value +pairs representing the columns of the table and the values you wish to +store. If the appropriate relationships are set up, foreign key fields +can also be passed an object representing the foreign row, and the +value will be set to its primary key. + +To create related objects, pass a hashref for the value if the related +item is a foreign key relationship (L), +and use the name of the relationship as the key. (NOT the name of the field, +necessarily). For C and C relationships, pass an arrayref +of hashrefs containing the data for each of the rows to create in the foreign +tables, again using the relationship name as the key. + +Instead of hashrefs of plain related data (key/value pairs), you may +also pass new or inserted objects. New objects (not inserted yet, see +L), will be inserted into their appropriate tables. Effectively a shortcut for C<< ->new_result(\%vals)->insert >>. +Example of creating a new row. + + $person_rs->create({ + name=>"Some Person", + email=>"somebody@someplace.com" + }); + +Example of creating a new row and also creating rows in a related C +or C resultset. Note Arrayref. + + $artist_rs->create( + { artistid => 4, name => 'Manufactured Crap', cds => [ + { title => 'My First CD', year => 2006 }, + { title => 'Yet More Tweeny-Pop crap', year => 2007 }, + ], + }, + ); + +Example of creating a new row and also creating a row in a related +Cresultset. Note Hashref. + + $cd_rs->create({ + title=>"Music for Silly Walks", + year=>2000, + artist => { + name=>"Silly Musician", + } + }); + =cut sub create { @@ -1395,13 +1838,14 @@ sub create { =item Arguments: \%vals, \%attrs? -=item Return Value: $object +=item Return Value: $rowobject =back - $class->find_or_create({ key => $val, ... }); + $cd->cd_to_producer->find_or_create({ producer => $producer }, + { key => 'primary }); -Tries to find a record based on its primary key or unique constraint; if none +Tries to find a record based on its primary key or unique constraints; if none is found, creates one and returns that instead. my $cd = $schema->resultset('CD')->find_or_create({ @@ -1422,6 +1866,18 @@ constraint. For example: { key => 'cd_artist_title' } ); +B: Because find_or_create() reads from the database and then +possibly inserts based on the result, this method is subject to a race +condition. Another process could create a record in the table after +the find has completed and before the create has started. To avoid +this problem, use find_or_create() inside a transaction. + +B: C is probably not what you want when creating +a new row in a table that uses primary keys supplied by the +database. Passing in a primary key column with a value of I +will cause L to attempt to search for a row with a value of +I. + See also L and L. For information on how to declare unique constraints, see L. @@ -1441,11 +1897,11 @@ sub find_or_create { =item Arguments: \%col_values, { key => $unique_constraint }? -=item Return Value: $object +=item Return Value: $rowobject =back - $class->update_or_create({ col => $val, ... }); + $resultset->update_or_create({ col => $val, ... }); First, searches for an existing row matching one of the unique constraints (including the primary key) on the source of this resultset. If a row is @@ -1465,6 +1921,14 @@ For example: { key => 'cd_artist_title' } ); + $cd->cd_to_producer->update_or_create({ + producer => $producer, + name => 'harry', + }, { + key => 'primary, + }); + + If no C is specified, it searches on all unique constraints defined on the source, including the primary key. @@ -1473,6 +1937,12 @@ If the C is specified as C, it searches only on the primary key. See also L and L. For information on how to declare unique constraints, see L. +B: C is probably not what you want when +looking for a row in a table that uses primary keys supplied by the +database, unless you actually have a key value. Passing in a primary +key column with a value of I will cause L to attempt to +search for a row with a value of I. + =cut sub update_or_create { @@ -1501,6 +1971,9 @@ sub update_or_create { Gets the contents of the cache for the resultset, if the cache is set. +The cache is populated either by using the L attribute to +L or by calling L. + =cut sub get_cache { @@ -1522,6 +1995,9 @@ 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. +The contents of the cache can also be populated by using the +L attribute to L. + =cut sub set_cache { @@ -1573,7 +2049,7 @@ sub related_resultset { my $rel_obj = $self->result_source->relationship_info($rel); $self->throw_exception( - "search_related: result source '" . $self->_source_handle->source_moniker . + "search_related: result source '" . $self->result_source->source_name . "' has no such relationship $rel") unless $rel_obj; @@ -1582,21 +2058,93 @@ sub related_resultset { my $join_count = $seen->{$rel}; my $alias = ($join_count > 1 ? join('_', $rel, $join_count) : $rel); - $self->_source_handle->schema->resultset($rel_obj->{class})->search_rs( - undef, { - %{$self->{attrs}||{}}, - join => undef, - prefetch => undef, - select => undef, - as => undef, - alias => $alias, - where => $self->{cond}, - seen_join => $seen, - from => $from, - }); + #XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi + my %attrs = %{$self->{attrs}||{}}; + delete @attrs{qw(result_class alias)}; + + my $new_cache; + + if (my $cache = $self->get_cache) { + if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) { + $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} } + @$cache ]; + } + } + + my $rel_source = $self->result_source->related_source($rel); + + my $new = do { + + # The reason we do this now instead of passing the alias to the + # search_rs below is that if you wrap/overload resultset on the + # source you need to know what alias it's -going- to have for things + # to work sanely (e.g. RestrictWithObject wants to be able to add + # extra query restrictions, and these may need to be $alias.) + + my $attrs = $rel_source->resultset_attributes; + local $attrs->{alias} = $alias; + + $rel_source->resultset + ->search_rs( + undef, { + %attrs, + join => undef, + prefetch => undef, + select => undef, + as => undef, + where => $self->{cond}, + seen_join => $seen, + from => $from, + }); + }; + $new->set_cache($new_cache) if $new_cache; + $new; }; } +=head2 current_source_alias + +=over 4 + +=item Arguments: none + +=item Return Value: $source_alias + +=back + +Returns the current table alias for the result source this resultset is built +on, that will be used in the SQL query. Usually it is C. + +Currently the source alias that refers to the result set returned by a +L/L family method depends on how you got to the resultset: it's +C by default, but eg. L aliases it to the related result +source name (and keeps C referring to the original result set). The long +term goal is to make L always alias the current resultset as C +(and make this method unnecessary). + +Thus it's currently necessary to use this method in predefined queries (see +L) when referring to the +source alias of the current result set: + + # in a result set class + sub modified_by { + my ($self, $user) = @_; + + my $me = $self->current_source_alias; + + return $self->search( + "$me.modified" => $user->id, + ); + } + +=cut + +sub current_source_alias { + my ($self) = @_; + + return ($self->{attrs} || {})->{alias} || 'me'; +} + sub _resolve_from { my ($self, $extra_join) = @_; my $source = $self->result_source; @@ -1610,9 +2158,14 @@ sub _resolve_from { my $join = ($attrs->{join} ? [ $attrs->{join}, $extra_join ] : $extra_join); + + # we need to take the prefetch the attrs into account before we + # ->resolve_join as otherwise they get lost - captainL + my $merged = $self->_merge_attr( $join, $attrs->{prefetch} ); + $from = [ @$from, - ($join ? $source->resolve_join($join, $attrs->{alias}, $seen) : ()), + ($join ? $source->resolve_join($merged, $attrs->{alias}, $seen) : ()), ]; return ($from,$seen); @@ -1673,6 +2226,7 @@ sub _resolved_attrs { $join = $self->_merge_attr( $join, $attrs->{prefetch} ); + } $attrs->{from} = # have to copy here to avoid corrupting the original @@ -1680,6 +2234,7 @@ sub _resolved_attrs { @{$attrs->{from}}, $source->resolve_join($join, $alias, { %{$attrs->{seen_join}||{}} }) ]; + } $attrs->{group_by} ||= $attrs->{select} if delete $attrs->{distinct}; @@ -1695,7 +2250,7 @@ sub _resolved_attrs { if (my $prefetch = delete $attrs->{prefetch}) { $prefetch = $self->_merge_attr({}, $prefetch); my @pre_order; - my $seen = $attrs->{seen_join} || {}; + my $seen = { %{ $attrs->{seen_join} || {} } }; foreach my $p (ref $prefetch eq 'ARRAY' ? @$prefetch : ($prefetch)) { # bring joins back to level of current class my @prefetch = $source->resolve_prefetch( @@ -1708,51 +2263,117 @@ sub _resolved_attrs { } $attrs->{collapse} = $collapse; + if ($attrs->{page}) { + $attrs->{offset} ||= 0; + $attrs->{offset} += ($attrs->{rows} * ($attrs->{page} - 1)); + } + return $self->{_attrs} = $attrs; } -sub _merge_attr { - my ($self, $a, $b) = @_; - return $b unless defined($a); - return $a unless defined($b); +sub _rollout_attr { + my ($self, $attr) = @_; - if (ref $b eq 'HASH' && ref $a eq 'HASH') { - foreach my $key (keys %{$b}) { - if (exists $a->{$key}) { - $a->{$key} = $self->_merge_attr($a->{$key}, $b->{$key}); + if (ref $attr eq 'HASH') { + return $self->_rollout_hash($attr); + } elsif (ref $attr eq 'ARRAY') { + return $self->_rollout_array($attr); + } else { + return [$attr]; + } +} + +sub _rollout_array { + my ($self, $attr) = @_; + + my @rolled_array; + foreach my $element (@{$attr}) { + if (ref $element eq 'HASH') { + push( @rolled_array, @{ $self->_rollout_hash( $element ) } ); + } elsif (ref $element eq 'ARRAY') { + # XXX - should probably recurse here + push( @rolled_array, @{$self->_rollout_array($element)} ); + } else { + push( @rolled_array, $element ); + } + } + return \@rolled_array; +} + +sub _rollout_hash { + my ($self, $attr) = @_; + + my @rolled_array; + foreach my $key (keys %{$attr}) { + push( @rolled_array, { $key => $attr->{$key} } ); + } + return \@rolled_array; +} + +sub _calculate_score { + my ($self, $a, $b) = @_; + + if (ref $b eq 'HASH') { + my ($b_key) = keys %{$b}; + if (ref $a eq 'HASH') { + my ($a_key) = keys %{$a}; + if ($a_key eq $b_key) { + return (1 + $self->_calculate_score( $a->{$a_key}, $b->{$b_key} )); } else { - $a->{$key} = $b->{$key}; + return 0; } - } - return $a; + } else { + return ($a eq $b_key) ? 1 : 0; + } } else { - $a = [$a] unless ref $a eq 'ARRAY'; - $b = [$b] unless ref $b eq 'ARRAY'; - - my $hash = {}; - my @array; - foreach my $x ($a, $b) { - foreach my $element (@{$x}) { - if (ref $element eq 'HASH') { - $hash = $self->_merge_attr($hash, $element); - } elsif (ref $element eq 'ARRAY') { - push(@array, @{$element}); - } else { - push(@array, $element) unless $b == $x - && grep { $_ eq $element } @array; - } + if (ref $a eq 'HASH') { + my ($a_key) = keys %{$a}; + return ($b eq $a_key) ? 1 : 0; + } else { + return ($b eq $a) ? 1 : 0; + } + } +} + +sub _merge_attr { + my ($self, $orig, $import) = @_; + + return $import unless defined($orig); + return $orig unless defined($import); + + $orig = $self->_rollout_attr($orig); + $import = $self->_rollout_attr($import); + + my $seen_keys; + foreach my $import_element ( @{$import} ) { + # find best candidate from $orig to merge $b_element into + my $best_candidate = { position => undef, score => 0 }; my $position = 0; + foreach my $orig_element ( @{$orig} ) { + my $score = $self->_calculate_score( $orig_element, $import_element ); + if ($score > $best_candidate->{score}) { + $best_candidate->{position} = $position; + $best_candidate->{score} = $score; } + $position++; } - - @array = grep { !exists $hash->{$_} } @array; - - return keys %{$hash} - ? ( scalar(@array) - ? [$hash, @array] - : $hash - ) - : \@array; + my ($import_key) = ( ref $import_element eq 'HASH' ) ? keys %{$import_element} : ($import_element); + + if ($best_candidate->{score} == 0 || exists $seen_keys->{$import_key}) { + push( @{$orig}, $import_element ); + } else { + my $orig_best = $orig->[$best_candidate->{position}]; + # merge orig_best and b_element together and replace original with merged + if (ref $orig_best ne 'HASH') { + $orig->[$best_candidate->{position}] = $import_element; + } elsif (ref $import_element eq 'HASH') { + my ($key) = keys %{$orig_best}; + $orig->[$best_candidate->{position}] = { $key => $self->_merge_attr($orig_best->{$key}, $import_element->{$key}) }; + } + } + $seen_keys->{$import_key} = 1; # don't merge the same key twice } + + return $orig; } sub result_source { @@ -1773,15 +2394,24 @@ See L for details. sub throw_exception { my $self=shift; - $self->_source_handle->schema->throw_exception(@_); + if (ref $self && $self->_source_handle->schema) { + $self->_source_handle->schema->throw_exception(@_) + } else { + croak(@_); + } + } # XXX: FIXME: Attributes docs need clearing up =head1 ATTRIBUTES -The resultset takes various attributes that modify its behavior. Here's an -overview of them: +Attributes are used to refine a ResultSet in various ways when +searching for data. They can be passed to any method which takes an +C<\%attrs> argument. See L, L, L, +L. + +These are in no particular order: =head2 order_by @@ -1800,6 +2430,10 @@ L) you will need to do C<\'year DESC' > specify an order. (The scalar ref causes it to be passed as raw sql to the DB, so you will need to manually quote things as appropriate.) +If your L version supports it (>=1.50), you can also use +C<{-desc => 'year'}>, which takes care of the quoting for you. This is the +recommended syntax. + =head2 columns =over 4 @@ -1862,7 +2496,7 @@ return a column named C in the above example. =over 4 Indicates additional columns to be selected from storage. Works the same as -L but adds columns to the selection. =back @@ -1870,7 +2504,7 @@ L. -The C< as > attribute is used in conjunction with C, usually when C +attributes will be ignored. =head2 page @@ -2244,6 +2894,69 @@ with a father in the person table, we could explicitly use C: # SELECT child.* FROM person child # INNER JOIN person father ON child.father_id = father.id +If you need to express really complex joins or you need a subselect, you +can supply literal SQL to C via a scalar reference. In this case +the contents of the scalar will replace the table name asscoiated with the +resultsource. + +WARNING: This technique might very well not work as expected on chained +searches - you have been warned. + + # Assuming the Event resultsource is defined as: + + MySchema::Event->add_columns ( + sequence => { + data_type => 'INT', + is_auto_increment => 1, + }, + location => { + data_type => 'INT', + }, + type => { + data_type => 'INT', + }, + ); + MySchema::Event->set_primary_key ('sequence'); + + # This will get back the latest event for every location. The column + # selector is still provided by DBIC, all we do is add a JOIN/WHERE + # combo to limit the resultset + + $rs = $schema->resultset('Event'); + $table = $rs->result_source->name; + $latest = $rs->search ( + undef, + { from => \ " + (SELECT e1.* FROM $table e1 + JOIN $table e2 + ON e1.location = e2.location + AND e1.sequence < e2.sequence + WHERE e2.sequence is NULL + ) me", + }, + ); + + # Equivalent SQL (with the DBIC chunks added): + + SELECT me.sequence, me.location, me.type FROM + (SELECT e1.* FROM events e1 + JOIN events e2 + ON e1.location = e2.location + AND e1.sequence < e2.sequence + WHERE e2.sequence is NULL + ) me; + +=head2 for + +=over 4 + +=item Value: ( 'update' | 'shared' ) + +=back + +Set to 'update' for a SELECT ... FOR UPDATE or 'shared' for a SELECT +... FOR SHARED. + =cut 1;