# Run the query, passing the result_class since it should propagate for find
my $rs = $self->search ($final_cond, {result_class => $self->result_class, %$attrs});
- if (keys %{$rs->_resolved_attrs->{collapse}}) {
+ if ($rs->_resolved_attrs->{collapse}) {
my $row = $rs->next;
carp "Query returned more than one row" if $rs->next;
return $row;
=over 4
-=item Arguments: $rel, $cond, \%attrs?
+=item Arguments: $rel, $cond?, \%attrs?
=item Return Value: $new_resultset (scalar context) || @row_objs (list context)
my $attrs = $self->_resolved_attrs_copy;
- if (keys %{$attrs->{collapse}}) {
- $self->throw_exception(
- 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
- );
- }
+ $self->throw_exception(
+ 'single() can not be used on resultsets prefetching has_many. Use find( \%cond ) or next() instead'
+ ) if $attrs->{collapse};
if ($where) {
if (defined $attrs->{where}) {
}
}
- my @data = $self->result_source->storage->select_single(
+ my $data = [ $self->result_source->storage->select_single(
$attrs->{from}, $attrs->{select},
$attrs->{where}, $attrs
- );
+ )];
- return (@data ? ($self->_construct_object(@data))[0] : undef);
+ return @$data ? $self->_construct_objects($data)->[0] : undef;
}
sub next {
my ($self) = @_;
+
if (my $cache = $self->get_cache) {
$self->{all_cache_position} ||= 0;
return $cache->[$self->{all_cache_position}++];
}
+
if ($self->{attrs}{cache}) {
delete $self->{pager};
$self->{all_cache_position} = 1;
return ($self->all)[0];
}
- if ($self->{stashed_objects}) {
- my $obj = shift(@{$self->{stashed_objects}});
- delete $self->{stashed_objects} unless @{$self->{stashed_objects}};
- return $obj;
- }
- my @row = (
- exists $self->{stashed_row}
- ? @{delete $self->{stashed_row}}
- : $self->cursor->next
- );
- return undef unless (@row);
- my ($row, @more) = $self->_construct_object(@row);
- $self->{stashed_objects} = \@more if @more;
- return $row;
-}
-
-sub _construct_object {
- my ($self, @row) = @_;
-
- my $info = $self->_collapse_result($self->{_attrs}{as}, \@row)
- or return ();
- 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_proto, $row) = @_;
-
- my @copy = @$row;
- # 'foo' => [ undef, 'foo' ]
- # 'foo.bar' => [ 'foo', 'bar' ]
- # 'foo.bar.baz' => [ 'foo.bar', 'baz' ]
+ return shift(@{$self->{stashed_objects}}) if @{ $self->{stashed_objects}||[] };
- my @construct_as = map { [ (/^(?:(.*)\.)?([^.]+)$/) ] } @$as_proto;
+ $self->{stashed_objects} = $self->_construct_objects
+ or return undef;
- my %collapse = %{$self->{_attrs}{collapse}||{}};
-
- my @pri_index;
-
- # if we're doing collapsing (has_many prefetch) we need to grab records
- # until the PK changes, so fill @pri_index. if not, we leave it empty so
- # we know we don't have to bother.
-
- # the reason for not using the collapse stuff directly is because if you
- # had for e.g. two artists in a row with no cds, the collapse info for
- # both would be NULL (undef) so you'd lose the second artist
+ return shift @{$self->{stashed_objects}};
+}
- # store just the index so we can check the array positions from the row
- # without having to contruct the full hash
+# takes a single DBI-row of data and coinstructs as many objects
+# as the resultset attributes call for.
+# This can be a bit of an action at a distance - it takes as an argument
+# the *current* cursor-row (already taken off the $sth), but if
+# collapsing is requested it will keep advancing the cursor either
+# until the current row-object is assembled (the collapser was able to
+# order the result sensibly) OR until the cursor is exhausted (an
+# unordered collapsing resultset effectively triggers ->all)
+sub _construct_objects {
+ my ($self, $fetched_row, $fetch_all) = @_;
- if (keys %collapse) {
- my %pri = map { ($_ => 1) } $self->result_source->_pri_cols;
- foreach my $i (0 .. $#construct_as) {
- next if defined($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!)
- }
+ my $attrs = $self->_resolved_attrs;
+ my $unordered = 0; # will deal with this later
+
+ # this will be used as both initial raw-row collector AND as a RV of
+ # _construct_objects. Not regrowing the # array twice matters a lot...
+ # a suprising amount actually
+ my $rows;
+
+ # $fetch_all implies all() which means all stashes have been cleared
+ # and the cursor reset
+ if ($fetch_all) {
+ # FIXME - we can do better, cursor->all (well a diff. method) should return a ref
+ $rows = [ $self->cursor->all ];
+ }
+ elsif ($unordered) {
+ $rows = [
+ $fetched_row||(),
+ @{ delete $self->{stashed_rows} || []},
+ $self->cursor->all,
+ ];
+ }
+ else { # simple single object
+ $rows = [ $fetched_row || ( @{$self->{stashed_rows}||[]} ? shift @{$self->{stashed_rows}} : [$self->cursor->next] ) ];
}
- # no need to do an if, it'll be empty if @pri_index is empty anyway
-
- my %pri_vals = map { ($_ => $copy[$_]) } @pri_index;
-
- my @const_rows;
-
- do { # no need to check anything at the front, we always want the first row
-
- my %const;
+ return undef unless @{$rows->[0]||[]};
- foreach my $this_as (@construct_as) {
- $const{$this_as->[0]||''}{$this_as->[1]} = shift(@copy);
+ my $rsrc = $self->result_source;
+ my $res_class = $self->result_class;
+ my $inflator = $res_class->can ('inflate_result')
+ or $self->throw_exception("Inflator $res_class does not provide an inflate_result() method");
+
+ # construct a much simpler array->hash folder for the one-table cases right here
+ if ($attrs->{_single_object_inflation} and ! $attrs->{collapse}) {
+ # FIXME this is a very very very hot spot
+ # while rather optimal we can *still* do much better, by
+ # building a smarter [Row|HRI]::inflate_result(), and
+ # switch to feeding it data via some leaner interface
+ #
+ my $infmap = $attrs->{as};
+ my @as_idx = 0..$#$infmap;
+ for my $r (@$rows) {
+ $r = [{ map { $infmap->[$_] => $r->[$_] } @as_idx }]
}
- push(@const_rows, \%const);
-
- } until ( # no pri_index => no collapse => drop straight out
- !@pri_index
- or
- do { # get another row, stash it, drop out if different PK
-
- @copy = $self->cursor->next;
- $self->{stashed_row} = \@copy;
-
- # last thing in do block, counts as true if anything doesn't match
-
- # check xor defined first for NULL vs. NOT NULL then if one is
- # defined the other must be so check string equality
-
- grep {
- (defined $pri_vals{$_} ^ defined $copy[$_])
- || (defined $pri_vals{$_} && ($pri_vals{$_} ne $copy[$_]))
- } @pri_index;
- }
- );
-
- my $alias = $self->{attrs}{alias};
- my $info = [];
-
- my %collapse_pos;
+ # FIXME - this seems to be faster than the hashmapper aove, especially
+ # on more rows, but need a better bench-environment to confirm
+ #eval sprintf (
+ # '$_ = [{ %s }] for @$rows',
+ # join (', ', map { "\$infmap->[$_] => \$_->[$_]" } 0..$#$infmap )
+ #);
+ }
+ else {
+ push @$rows, @{$self->{stashed_rows}||[]};
+
+ $rsrc->_mk_row_parser({
+ inflate_map => $attrs->{as},
+ selection => $attrs->{select},
+ collapse => $attrs->{collapse},
+ unordered => $unordered,
+ })->(
+ $rows, # modify in-place, shrinking/extending as necessary
+ ($attrs->{collapse} and ! $fetch_all and ! $unordered)
+ ? (
+ sub { my @r = $self->cursor->next or return undef; \@r },
+ ($self->{stashed_rows} = []), # this is where we empty things and prepare for leftovers
+ )
+ : ()
+ ,
+ );
+ }
- my @const_keys;
+ $_ = $res_class->$inflator($rsrc, @$_) for @$rows;
- 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};
- }
- }
+ # CDBI compat stuff
+ if ($attrs->{record_filter}) {
+ $_ = $attrs->{record_filter}->($_) for @$rows;
}
- return $info;
+ return $rows;
}
=head2 result_source
# extra selectors do not go in the subquery and there is no point of ordering it, nor locking it
delete @{$sub_attrs}{qw/collapse columns as select _prefetch_selector_range order_by for/};
- # if we multi-prefetch we group_by primary keys only as this is what we would
+ # if we multi-prefetch we group_by something unique, as this is what we would
# get out of the rs via ->next/->all. We *DO WANT* to clobber old group_by regardless
- if ( keys %{$attrs->{collapse}} ) {
- $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } ($rsrc->_pri_cols) ]
+ if ( $attrs->{collapse} ) {
+ $sub_attrs->{group_by} = [ map { "$attrs->{alias}.$_" } @{
+ $rsrc->_identifying_column_set || $self->throw_exception(
+ 'Unable to construct a unique group_by criteria properly collapsing the '
+ . 'has_many prefetch before count()'
+ );
+ } ]
}
# Calculate subquery selector
sub all {
my $self = shift;
if(@_) {
- $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
+ $self->throw_exception("all() doesn't take any arguments, you probably wanted ->search(...)->all()");
}
- return @{ $self->get_cache } if $self->get_cache;
-
- my @obj;
-
- if (keys %{$self->_resolved_attrs->{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;
+ delete $self->{stashed_rows};
+ delete $self->{stashed_objects};
+
+ if (my $c = $self->get_cache) {
+ return @$c;
}
- $self->set_cache(\@obj) if $self->{attrs}{cache};
+ $self->cursor->reset;
+
+ my $objs = $self->_construct_objects(undef, 'fetch_all') || [];
+
+ $self->set_cache($objs) if $self->{attrs}{cache};
- return @obj;
+ return @$objs;
}
=head2 reset
sub reset {
my ($self) = @_;
- delete $self->{_attrs} if exists $self->{_attrs};
+ delete $self->{_attrs};
+ delete $self->{stashed_rows};
+ delete $self->{stashed_objects};
+
$self->{all_cache_position} = 0;
$self->cursor->reset;
return $self;
}
# we got this far - means it is time to wrap a subquery
- my $pcols = [ $rsrc->_pri_cols ];
+ my $idcols = $rsrc->_identifying_column_set || $self->throw_exception(
+ sprintf(
+ "Unable to perform complex resultset %s() without an identifying set of columns on source '%s'",
+ $op,
+ $rsrc->source_name,
+ )
+ );
my $existing_group_by = delete $attrs->{group_by};
# make a new $rs selecting only the PKs (that's all we really need for the subq)
- delete $attrs->{$_} for qw/collapse _collapse_order_by select _prefetch_selector_range as/;
- $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$pcols ];
+ delete $attrs->{$_} for qw/collapse select _prefetch_selector_range as/;
+ $attrs->{columns} = [ map { "$attrs->{alias}.$_" } @$idcols ];
$attrs->{group_by} = \ ''; # FIXME - this is an evil hack, it causes the optimiser to kick in and throw away the LEFT joins
my $subrs = (ref $self)->new($rsrc, $attrs);
- if (@$pcols == 1) {
+ if (@$idcols == 1) {
return $storage->$op (
$rsrc,
$op eq 'update' ? $values : (),
- { $pcols->[0] => { -in => $subrs->as_query } },
+ { $idcols->[0] => { -in => $subrs->as_query } },
);
}
elsif ($storage->_use_multicolumn_in) {
my $sql_maker = $storage->sql_maker;
my ($sql, @bind) = @${$subrs->as_query};
$sql = sprintf ('(%s) IN %s', # the as_query already comes with a set of parenthesis
- join (', ', map { $sql_maker->_quote ($_) } @$pcols),
+ join (', ', map { $sql_maker->_quote ($_) } @$idcols),
$sql,
);
my @op_condition;
for my $row ($subrs->search({}, { group_by => $subq_group_by })->cursor->all) {
push @op_condition, { map
- { $pcols->[$_] => $row->[$_] }
- (0 .. $#$pcols)
+ { $idcols->[$_] => $row->[$_] }
+ (0 .. $#$idcols)
};
}
See also L</find> and L</update_or_create>. For information on how to declare
unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
+If you need to know if an existing row was found or a new one created use
+L</find_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
+to call L<DBIx::Class::Row/insert> to save the newly created row to the
+database!
+
+ my $cd = $schema->resultset('CD')->find_or_new({
+ cdid => 5,
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ year => 2005,
+ });
+
+ if( $cd->in_storage ) {
+ # do some stuff
+ $cd->insert;
+ }
+
=cut
sub find_or_create {
See also L</find> and L</find_or_create>. For information on how to declare
unique constraints, see L<DBIx::Class::ResultSource/add_unique_constraint>.
+If you need to know if an existing row was updated or a new one created use
+L</update_or_new> and L<DBIx::Class::Row/in_storage> instead. Don't forget
+to call L<DBIx::Class::Row/insert> to save the newly created row to the
+database!
+
+ my $cd = $schema->resultset('CD')->update_or_new(
+ {
+ artist => 'Massive Attack',
+ title => 'Mezzanine',
+ year => 1998,
+ },
+ { key => 'cd_artist_title' }
+ );
+
+ if( $cd->in_storage ) {
+ # do some stuff
+ $cd->insert;
+ }
+
=cut
sub update_or_create {
if (my $cache = $self->get_cache) {
if ($cache->[0] && $cache->[0]->related_resultset($rel)->get_cache) {
- $new_cache = [ map { @{$_->related_resultset($rel)->get_cache} }
+ $new_cache = [ map { @{$_->related_resultset($rel)->get_cache||[]} }
@$cache ];
}
}
my $me = $self->current_source_alias;
- return $self->search(
+ return $self->search({
"$me.modified" => $user->id,
- );
+ });
}
=cut
if $attrs->{select};
# assume all unqualified selectors to apply to the current alias (legacy stuff)
- for (@sel) {
- $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_";
- }
+ $_ = (ref $_ or $_ =~ /\./) ? $_ : "$alias.$_" for @sel;
- # disqualify all $alias.col as-bits (collapser mandated)
- for (@as) {
- $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_;
- }
+ # disqualify all $alias.col as-bits (inflate-map mandated)
+ $_ = ($_ =~ /^\Q$alias.\E(.+)$/) ? $1 : $_ for @as;
# de-duplicate the result (remove *identical* select/as pairs)
# and also die on duplicate {as} pointing to different {select}s
}
}
- $attrs->{collapse} ||= {};
- if ($attrs->{prefetch}) {
+ # generate selections based on the prefetch helper
+ my $prefetch;
+ $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} )
+ if defined $attrs->{prefetch};
+
+ if ($prefetch) {
$self->throw_exception("Unable to prefetch, resultset contains an unnamed selector $attrs->{_dark_selector}{string}")
if $attrs->{_dark_selector};
- my $prefetch = $self->_merge_joinpref_attr( {}, delete $attrs->{prefetch} );
-
- my $prefetch_ordering = [];
+ $attrs->{collapse} = 1;
# this is a separate structure (we don't look in {from} directly)
# as the resolver needs to shift things off the lists to work
}
}
- my @prefetch =
- $source->_resolve_prefetch( $prefetch, $alias, $join_map, $prefetch_ordering, $attrs->{collapse} );
+ my @prefetch = $source->_resolve_prefetch( $prefetch, $alias, $join_map );
# we need to somehow mark which columns came from prefetch
if (@prefetch) {
push @{ $attrs->{select} }, (map { $_->[0] } @prefetch);
push @{ $attrs->{as} }, (map { $_->[1] } @prefetch);
+ }
+
+ # run through the resulting joinstructure (starting from our current slot)
+ # and unset collapse if proven unnesessary
+ if ($attrs->{collapse} && ref $attrs->{from} eq 'ARRAY') {
+
+ if (@{$attrs->{from}} > 1) {
+
+ # find where our table-spec starts and consider only things after us
+ my @fromlist = @{$attrs->{from}};
+ while (@fromlist) {
+ my $t = shift @fromlist;
+ $t = $t->[0] if ref $t eq 'ARRAY'; #me vs join from-spec mismatch
+ last if ($t->{-alias} && $t->{-alias} eq $alias);
+ }
- push( @{$attrs->{order_by}}, @$prefetch_ordering );
- $attrs->{_collapse_order_by} = \@$prefetch_ordering;
+ for (@fromlist) {
+ $attrs->{collapse} = ! $_->[0]{-is_single}
+ and last;
+ }
+ }
+ else {
+ # no joins - no collapse
+ $attrs->{collapse} = 0;
+ }
}
+ $attrs->{_single_object_inflation} = ! List::Util::first { $_ =~ /\./ } @{$attrs->{as}};
# if both page and offset are specified, produce a combined offset
# even though it doesn't make much sense, this is what pre 081xx has
Specifies the (zero-based) row number for the first row to be returned, or the
of the first row of the first page if paging is used.
+=head2 software_limit
+
+=over 4
+
+=item Value: (0 | 1)
+
+=back
+
+When combined with L</rows> and/or L</offset> the generated SQL will not
+include any limit dialect stanzas. Instead the entire result will be selected
+as if no limits were specified, and DBIC will perform the limit locally, by
+artificially advancing and finishing the resulting L</cursor>.
+
+This is the recommended way of performing resultset limiting when no sane RDBMS
+implementation is available (e.g.
+L<Sybase ASE|DBIx::Class::Storage::DBI::Sybase::ASE> using the
+L<Generic Sub Query|DBIx::Class::SQLMaker::LimitDialects/GenericSubQ> hack)
+
=head2 group_by
=over 4
projects / dbsrgits/DBIx-Class.git / blobdiff