use DBIx::Class::ResultSetColumn;
use DBIx::Class::ResultSourceHandle;
use List::Util ();
-use Scalar::Util 'blessed';
+use Scalar::Util qw/blessed weaken/;
+use Try::Tiny;
use namespace::clean;
use overload
return $cache->[$self->{all_cache_position}++];
}
if ($self->{attrs}{cache}) {
+ delete $self->{pager};
$self->{all_cache_position} = 1;
return ($self->all)[0];
}
=cut
+# make a wizard good for both a scalar and a hashref
+my $mk_lazy_count_wizard = sub {
+ require Variable::Magic;
+
+ my $stash = { total_rs => shift };
+ my $slot = shift; # only used by the hashref magic
+
+ my $magic = Variable::Magic::wizard (
+ data => sub { $stash },
+
+ (!$slot)
+ ? (
+ # the scalar magic
+ get => sub {
+ # set value lazily, and dispell for good
+ ${$_[0]} = $_[1]{total_rs}->count;
+ Variable::Magic::dispell (${$_[0]}, $_[1]{magic_selfref});
+ return 1;
+ },
+ set => sub {
+ # an explicit set implies dispell as well
+ # the unless() is to work around "fun and giggles" below
+ Variable::Magic::dispell (${$_[0]}, $_[1]{magic_selfref})
+ unless (caller(2))[3] eq 'DBIx::Class::ResultSet::pager';
+ return 1;
+ },
+ )
+ : (
+ # the uvar magic
+ fetch => sub {
+ if ($_[2] eq $slot and !$_[1]{inactive}) {
+ my $cnt = $_[1]{total_rs}->count;
+ $_[0]->{$slot} = $cnt;
+
+ # attempting to dispell in a fetch handle (works in store), seems
+ # to invariable segfault on 5.10, 5.12, 5.13 :(
+ # so use an inactivator instead
+ #Variable::Magic::dispell (%{$_[0]}, $_[1]{magic_selfref});
+ $_[1]{inactive}++;
+ }
+ return 1;
+ },
+ store => sub {
+ if (! $_[1]{inactive} and $_[2] eq $slot) {
+ #Variable::Magic::dispell (%{$_[0]}, $_[1]{magic_selfref});
+ $_[1]{inactive}++
+ unless (caller(2))[3] eq 'DBIx::Class::ResultSet::pager';
+ }
+ return 1;
+ },
+ ),
+ );
+
+ $stash->{magic_selfref} = $magic;
+ weaken ($stash->{magic_selfref}); # this fails on 5.8.1
+
+ return $magic;
+};
+
+# the tie class for 5.8.1
+{
+ package DBIx::Class::__DBIC_LAZY_RS_COUNT__;
+ use base qw/Tie::Hash/;
+
+ sub FIRSTKEY { my $dummy = scalar keys %{$_[0]{data}}; each %{$_[0]{data}} }
+ sub NEXTKEY { each %{$_[0]{data}} }
+ sub EXISTS { exists $_[0]{data}{$_[1]} }
+ sub DELETE { delete $_[0]{data}{$_[1]} }
+ sub CLEAR { %{$_[0]{data}} = () }
+ sub SCALAR { scalar %{$_[0]{data}} }
+
+ sub TIEHASH {
+ $_[1]{data} = {%{$_[1]{selfref}}};
+ %{$_[1]{selfref}} = ();
+ Scalar::Util::weaken ($_[1]{selfref});
+ return bless ($_[1], $_[0]);
+ };
+
+ sub FETCH {
+ if ($_[1] eq $_[0]{slot}) {
+ my $cnt = $_[0]{data}{$_[1]} = $_[0]{total_rs}->count;
+ untie %{$_[0]{selfref}};
+ %{$_[0]{selfref}} = %{$_[0]{data}};
+ return $cnt;
+ }
+ else {
+ $_[0]{data}{$_[1]};
+ }
+ }
+
+ sub STORE {
+ $_[0]{data}{$_[1]} = $_[2];
+ if ($_[1] eq $_[0]{slot}) {
+ untie %{$_[0]{selfref}};
+ %{$_[0]{selfref}} = %{$_[0]{data}};
+ }
+ $_[2];
+ }
+}
+
sub pager {
my ($self) = @_;
return $self->{pager} if $self->{pager};
+ if ($self->get_cache) {
+ $self->throw_exception ('Pagers on cached resultsets are not supported');
+ }
+
my $attrs = $self->{attrs};
$self->throw_exception("Can't create pager for non-paged rs")
unless $self->{attrs}{page};
# with a subselect) to get the real total count
my $count_attrs = { %$attrs };
delete $count_attrs->{$_} for qw/rows offset page pager/;
- my $total_count = (ref $self)->new($self->result_source, $count_attrs)->count;
+ my $total_rs = (ref $self)->new($self->result_source, $count_attrs);
+
+
+### the following may seem awkward and dirty, but it's a thought-experiment
+### necessary for future development of DBIx::DS. Do *NOT* change this code
+### before talking to ribasushi/mst
- return $self->{pager} = Data::Page->new(
- $total_count,
+ my $pager = Data::Page->new(
+ 0, #start with an empty set
$attrs->{rows},
- $self->{attrs}{page}
+ $self->{attrs}{page},
);
+
+ my $data_slot = 'total_entries';
+
+ # Since we are interested in a cached value (once it's set - it's set), every
+ # technique will detach from the magic-host once the time comes to fire the
+ # ->count (or in the segfaulting case of >= 5.10 it will deactivate itself)
+
+ if ($] < 5.008003) {
+ # 5.8.1 throws 'Modification of a read-only value attempted' when one tries
+ # to weakref the magic container :(
+ # tested on 5.8.1
+ tie (%$pager, 'DBIx::Class::__DBIC_LAZY_RS_COUNT__',
+ { slot => $data_slot, total_rs => $total_rs, selfref => $pager }
+ );
+ }
+ elsif ($] < 5.010) {
+ # We can use magic on the hash value slot. It's interesting that the magic is
+ # attached to the hash-slot, and does *not* stop working once I do the dummy
+ # assignments after the cast()
+ # tested on 5.8.3 and 5.8.9
+ my $magic = $mk_lazy_count_wizard->($total_rs);
+ Variable::Magic::cast ( $pager->{$data_slot}, $magic );
+
+ # this is for fun and giggles
+ $pager->{$data_slot} = -1;
+ $pager->{$data_slot} = 0;
+
+ # this does not work for scalars, but works with
+ # uvar magic below
+ #my %vals = %$pager;
+ #%$pager = ();
+ #%{$pager} = %vals;
+ }
+ else {
+ # And the uvar magic
+ # works on 5.10.1, 5.12.1 and 5.13.4 in its current form,
+ # however see the wizard maker for more notes
+ my $magic = $mk_lazy_count_wizard->($total_rs, $data_slot);
+ Variable::Magic::cast ( %$pager, $magic );
+
+ # still works
+ $pager->{$data_slot} = -1;
+ $pager->{$data_slot} = 0;
+
+ # this now works
+ my %vals = %$pager;
+ %$pager = ();
+ %{$pager} = %vals;
+ }
+
+ return $self->{pager} = $pager;
}
=head2 page
# (the select/as attrs were deleted in the beginning), we need to flip all
# left joins to inner, so we get the expected results
# read the comment on top of the actual function to see what this does
- $attrs->{from} = $rsrc->schema->storage->_straight_join_to_node ($attrs->{from}, $alias);
+ $attrs->{from} = $rsrc->schema->storage->_inner_join_to_node ($attrs->{from}, $alias);
#XXX - temp fix for result_class bug. There likely is a more elegant fix -groditi
carp ("Useless use of distinct on a grouped resultset ('distinct' is ignored when a 'group_by' is present)");
}
else {
- $attrs->{group_by} = [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
+ my $storage = $self->result_source->schema->storage;
+ my $rs_column_list = $storage->_resolve_column_info ($attrs->{from});
+
+ my $group_spec = $attrs->{group_by} = [];
+ my %group_index;
+ for (@{$attrs->{select}}) {
+ if (! ref($_) or ref ($_) ne 'HASH' ) {
+ push @$group_spec, $_;
+ $group_index{$_}++;
+ if ($rs_column_list->{$_} and $_ !~ /\./ ) {
+ # add a fully qualified version as well
+ $group_index{"$rs_column_list->{$_}{-source_alias}.$_"}++;
+ }
+ }
+ }
# add any order_by parts that are not already present in the group_by
# we need to be careful not to add any named functions/aggregates
# i.e. select => [ ... { count => 'foo', -as 'foocount' } ... ]
- my %already_grouped = map { $_ => 1 } (@{$attrs->{group_by}});
-
- my $storage = $self->result_source->schema->storage;
+ for my $chunk ($storage->_parse_order_by($attrs->{order_by})) {
- my $rs_column_list = $storage->_resolve_column_info ($attrs->{from});
+ # only consider real columns (for functions the user got to do an explicit group_by)
+ my $colinfo = $rs_column_list->{$chunk}
+ or next;
- for my $chunk ($storage->_parse_order_by($attrs->{order_by})) {
- if ($rs_column_list->{$chunk} && not $already_grouped{$chunk}++) {
- push @{$attrs->{group_by}}, $chunk;
- }
+ $chunk = "$colinfo->{-source_alias}.$chunk" if $chunk !~ /\./;
+ push @$group_spec, $chunk unless $group_index{$chunk}++;
}
}
}
C<select> as normal. (You may also use the C<cols> attribute, as in
earlier versions of DBIC.)
+Essentially C<columns> does the same as L</select> and L</as>.
+
+ columns => [ 'foo', { bar => 'baz' } ]
+
+is the same as
+
+ select => [qw/foo baz/],
+ as => [qw/foo bar/]
+
=head2 +columns
=over 4
projects / dbsrgits/DBIx-Class.git / blobdiff