X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FResultSet.pm;h=282651f0cd1e5e8218d4d0c303a5bd404a78f52a;hb=194311161bdbebd2402c457ded300fc83b773f02;hp=13e11744ffd256e0d5f95847ac1c233dbf810e18;hpb=639cf8f9d212c3e950ae5bae680133762c1df0aa;p=dbsrgits%2FDBIx-Class.git

diff --git a/lib/DBIx/Class/ResultSet.pm b/lib/DBIx/Class/ResultSet.pm
index 13e1174..282651f 100644
--- a/lib/DBIx/Class/ResultSet.pm
+++ b/lib/DBIx/Class/ResultSet.pm
@@ -46,27 +46,13 @@ A new ResultSet is returned from calling L</search> on an existing
 ResultSet. The new one will contain all the conditions of the
 original, plus any new conditions added in the C<search> call.
 
-A ResultSet is also an iterator. L</next> is used to return all the
-L<DBIx::Class::Row>s the ResultSet represents.
+A ResultSet also incorporates an implicit iterator. L</next> and L</reset>
+can be used to walk through all the L<DBIx::Class::Row>s the ResultSet
+represents.
 
 The query that the ResultSet represents is B<only> executed against
 the database when these methods are called:
-
-=over
-
-=item L</find>
-
-=item L</next>
-
-=item L</all>
-
-=item L</count>
-
-=item L</single>
-
-=item L</first>
-
-=back
+L</find> L</next> L</all> L</first> L</single> L</count>
 
 =head1 EXAMPLES
 
@@ -674,7 +660,9 @@ L<DBIx::Class::Cursor> for more information.
 sub cursor {
   my ($self) = @_;
 
-  my $attrs = { %{$self->_resolved_attrs} };
+  my $attrs = $self->_resolved_attrs_copy;
+  $attrs->{_virtual_order_by} = $self->_gen_virtual_order;
+
   return $self->{cursor}
     ||= $self->result_source->storage->select($attrs->{from}, $attrs->{select},
           $attrs->{where},$attrs);
@@ -725,7 +713,9 @@ sub single {
       $self->throw_exception('single() only takes search conditions, no attributes. You want ->search( $cond, $attrs )->single()');
   }
 
-  my $attrs = { %{$self->_resolved_attrs} };
+  my $attrs = $self->_resolved_attrs_copy;
+  $attrs->{_virtual_order_by} = $self->_gen_virtual_order;
+
   if ($where) {
     if (defined $attrs->{where}) {
       $attrs->{where} = {
@@ -752,6 +742,16 @@ sub single {
   return (@data ? ($self->_construct_object(@data))[0] : undef);
 }
 
+# _gen_virtual_order
+#
+# This is a horrble hack, but seems like the best we can do at this point
+# Some limit emulations (Top) require an ordered resultset in order to 
+# function at all. So supply a PK order to be used if necessary
+
+sub _gen_virtual_order {
+  return [ shift->result_source->primary_columns ];
+}
+
 # _is_unique_query
 #
 # Try to determine if the specified query is guaranteed to be unique, based on
@@ -870,10 +870,10 @@ instead. An example conversion is:
 
 sub search_like {
   my $class = shift;
-  carp join ("\n",
-    'search_like() is deprecated and will be removed in 0.09.',
-    'Instead use ->search({ x => { -like => "y%" } })',
-    '(note the outer pair of {}s - they are important!)'
+  carp (
+    'search_like() is deprecated and will be removed in DBIC version 0.09.'
+   .' Instead use ->search({ x => { -like => "y%" } })'
+   .' (note the outer pair of {}s - they are important!)'
   );
   my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
   my $query = ref $_[0] eq 'HASH' ? { %{shift()} }: {@_};
@@ -1145,8 +1145,8 @@ sub result_class {
 =back
 
 Performs an SQL C<COUNT> with the same query as the resultset was built
-with to find the number of elements. If passed arguments, does a search
-on the resultset and counts the results of that.
+with to find the number of elements. Passing arguments is equivalent to
+C<< $rs->search ($cond, \%attrs)->count >>
 
 =cut
 
@@ -1155,39 +1155,53 @@ sub count {
   return $self->search(@_)->count if @_ and defined $_[0];
   return scalar @{ $self->get_cache } if $self->get_cache;
 
-  my @subq_attrs = qw/prefetch collapse distinct group_by having having_bind/;
+  my @grouped_subq_attrs = qw/prefetch collapse distinct group_by having/;
+  my @subq_attrs = ();
+  
   my $attrs = $self->_resolved_attrs;
-
   # if we are not paged - we are simply asking for a limit
   if (not $attrs->{page} and not $attrs->{software_limit}) {
     push @subq_attrs, qw/rows offset/;
   }
 
-  return $self->_has_attr (@subq_attrs)
-    ? $self->_count_subq
+  my $need_subq = $self->_has_attr (@subq_attrs);
+  my $need_group_subq = $self->_has_attr (@grouped_subq_attrs);
+
+  return ($need_subq || $need_group_subq)
+    ? $self->_count_subq ($need_group_subq)
     : $self->_count_simple
 }
 
 sub _count_subq {
-  my $self = shift;
+  my ($self, $add_group_by) = @_;
 
-  my $attrs = { %{$self->_resolved_attrs} };
+  my $attrs = $self->_resolved_attrs_copy;
 
   # copy for the subquery, we need to do some adjustments to it too
   my $sub_attrs = { %$attrs };
 
-  # these can not go in the subquery either
-  delete $sub_attrs->{$_} for qw/prefetch select +select as +as columns +columns/;
+  # these can not go in the subquery, and there is no point of ordering it
+  delete $sub_attrs->{$_} for qw/prefetch collapse select +select as +as columns +columns order_by/;
 
-  # force a group_by and the same set of columns (most databases require this)
-  $sub_attrs->{columns} = $sub_attrs->{group_by} ||= [ map { "$attrs->{alias}.$_" } ($self->result_source->primary_columns) ];
+  # if needed force a group_by and the same set of columns (most databases require this)
+  if ($add_group_by) {
+
+    # if we prefetch, we group_by primary keys only as this is what we would get out of the rs via ->next/->all
+    # simply deleting group_by suffices, as the code below will re-fill it
+    # Note: we check $attrs, as $sub_attrs has collapse deleted
+    if (ref $attrs->{collapse} and keys %{$attrs->{collapse}} ) { 
+      delete $sub_attrs->{group_by};
+    }
+
+    $sub_attrs->{columns} = $sub_attrs->{group_by} ||= [ map { "$attrs->{alias}.$_" } ($self->result_source->primary_columns) ];
+  }
 
   $attrs->{from} = [{
     count_subq => (ref $self)->new ($self->result_source, $sub_attrs )->as_query
   }];
 
   # the subquery replaces this
-  delete $attrs->{$_} for qw/where bind prefetch collapse group_by having/;
+  delete $attrs->{$_} for qw/where bind prefetch collapse distinct group_by having having_bind/;
 
   return $self->__count ($attrs);
 }
@@ -1200,9 +1214,10 @@ sub _count_simple {
 
   # 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;
+  my $attrs = $self->_resolved_attrs;
+
+  $count -= $attrs->{offset} if $attrs->{offset};
+  $count = $attrs->{rows} if $attrs->{rows} and $attrs->{rows} < $count;
   $count = 0 if ($count < 0);
   return $count;
 }
@@ -1210,7 +1225,7 @@ sub _count_simple {
 sub __count {
   my ($self, $attrs) = @_;
 
-  $attrs ||= { %{$self->_resolved_attrs} };
+  $attrs ||= $self->_resolved_attrs_copy;
 
   # take off any column specs, any pagers, record_filter is cdbi, and no point of ordering a count
   delete $attrs->{$_} for (qw/columns +columns select +select as +as rows offset page pager order_by record_filter/); 
@@ -1351,9 +1366,9 @@ sub _rs_update_delete {
   if ($needs_group_by_subq or $needs_subq) {
 
     # make a new $rs selecting only the PKs (that's all we really need)
-    my $attrs = $self->_resolved_attrs;
+    my $attrs = $self->_resolved_attrs_copy;
 
-    delete $attrs->{$_} for qw/prefetch select +select as +as columns +columns/;
+    delete $attrs->{$_} for qw/prefetch collapse select +select as +as columns +columns/;
     $attrs->{columns} = [ map { "$attrs->{alias}.$_" } ($self->result_source->primary_columns) ];
 
     if ($needs_group_by_subq) {
@@ -1512,7 +1527,7 @@ sub update_all {
 
 =item Arguments: none
 
-=item Return Value: 1
+=item Return Value: $storage_rv
 
 =back
 
@@ -1520,11 +1535,8 @@ Deletes the contents of the resultset from its result source. Note that this
 will not run DBIC cascade triggers. See L</delete_all> if you need triggers
 to run. See also L<DBIx::Class::Row/delete>.
 
-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:-
-
-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.
+Return value will be the amount of rows deleted; exact type of return value
+is storage-dependent.
 
 =cut
 
@@ -2509,6 +2521,12 @@ sub _resolve_from {
   return ($from,$seen);
 }
 
+# too many times we have to do $attrs = { %{$self->_resolved_attrs} }
+sub _resolved_attrs_copy {
+  my $self = shift;
+  return { %{$self->_resolved_attrs (@_)} };
+}
+
 sub _resolved_attrs {
   my $self = shift;
   return $self->{_attrs} if $self->{_attrs};
@@ -2609,8 +2627,6 @@ sub _resolved_attrs {
 
   }
 
-  $attrs->{group_by} ||= $attrs->{select}
-    if delete $attrs->{distinct};
   if ( $attrs->{order_by} ) {
     $attrs->{order_by} = (
       ref( $attrs->{order_by} ) eq 'ARRAY'
@@ -2637,6 +2653,11 @@ sub _resolved_attrs {
     }
     push( @{ $attrs->{order_by} }, @pre_order );
   }
+
+  if (delete $attrs->{distinct}) {
+    $attrs->{group_by} ||= [ grep { !ref($_) || (ref($_) ne 'HASH') } @{$attrs->{select}} ];
+  }
+
   $attrs->{collapse} = $collapse;
 
   if ( $attrs->{page} and not defined $attrs->{offset} ) {