Note that single expects a single row in the ResultSet docs

[dbsrgits/DBIx-Class.git] / lib / DBIx / Class / ResultSet.pm

diff --git a/lib/DBIx/Class/ResultSet.pm b/lib/DBIx/Class/ResultSet.pm
index 775d032..f56254e 100644 (file)
--- a/lib/DBIx/Class/ResultSet.pm
+++ b/lib/DBIx/Class/ResultSet.pm
@@ -332,11 +332,15 @@ Additionally, you can specify the columns explicitly by name:
 If the C<key> is specified as C<primary>, it searches only on the primary key.
 
 If no C<key> 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<must> provide a value for the
 C<key> attribute matching one of the unique constraints on the source.
 
+Note: If your query does not return only one row, a warning is generated:
+
+  Query returned more than one row
+
 See also L</find_or_create> and L</update_or_create>. For information on how to
 declare unique constraints, see
 L<DBIx::Class::ResultSource/add_unique_constraint>.
@@ -388,25 +392,46 @@ 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);
+    }
   }
 }
 
@@ -496,6 +521,17 @@ 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
@@ -535,9 +571,17 @@ sub cursor {
 Inflates the first result without creating a cursor if the resultset has
 any records in it; if not returns nothing. Used by L</find> as an optimisation.
 
-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.
+Can optionally take an additional condition B<only> - this is a fast-code-path
+method; if you need to add extra joins or similar call L</search> and then
+L</single> without a condition on the L<DBIx::Class::ResultSet> returned from
+that.
+
+B<Note>: As of 0.08100, this method assumes that the 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</first> or L</find> instead.
 
 =cut
 
@@ -2132,7 +2176,12 @@ See L<DBIx::Class::Schema/throw_exception> 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