This method specifies a value of L</position_column> which B<would
never be assigned to a row> during normal operation. When
a row is moved, its position is set to this value temporarily, so
-that any unique constrainst can not be violated. This value defaults
+that any unique constraints can not be violated. This value defaults
to 0, which should work for all cases except when your positions do
indeed start from 0.
sub move_to_group {
my( $self, $to_group, $to_position ) = @_;
- $self->throw_exception ('move_to_group() expects a group specification')
- unless defined $to_group;
-
- # if we're given a string, turn it into a hashref
+ # if we're given a single value, turn it into a hashref
unless (ref $to_group eq 'HASH') {
my @gcols = $self->_grouping_columns;
my @original_values = $cursor->next;
$self->set_inflated_columns ({ %values, map { $_ => shift @original_values } (@dirty_cols) });
+ delete $self->{_dirty_columns}{$_} for (@dirty_cols);
}
if ($self->_is_in_group ($to_group) ) {
}
else {
my $bumped_pos_val = $self->_position_value ($to_position);
- my @between = ($to_position, $new_group_last_position);
+ my @between = map { $self->_position_value ($_) } ($to_position, $new_group_last_position);
$self->_shift_siblings (1, @between); #shift right
$self->set_column( $position_column => $bumped_pos_val );
}
# these steps are necessary to keep the external appearance of
# ->update($upd) so that other things overloading update() will
# work properly
- my %original_values = $self->get_inflated_columns;
+ my %original_values = $self->get_columns;
my %existing_changes = $self->get_dirty_columns;
# See if any of the *supplied* changes would affect the ordering
if you are working with preexisting non-normalised position data,
or if you need to work with materialized path columns.
-=head2 _position
-
- my $num_pos = $item->_position;
-
-Returns the B<absolute numeric position> of the current object, with the
-first object being at position 1, its sibling at position 2 and so on.
-By default simply returns the value of L</position_column>.
-
-=cut
-sub _position {
- my $self = shift;
-
-# #the right way to do this
-# return $self->previous_siblings->count + 1;
-
- return $self->get_column ($self->position_column);
-}
-
=head2 _position_from_value
- my $num_pos = $item->_position_of_value ( $pos_value )
+ my $num_pos = $item->_position_from_value ( $pos_value )
Returns the B<absolute numeric position> of an object with a B<position
value> set to C<$pos_value>. By default simply returns C<$pos_value>.
if (grep { $_ eq $position_column } ( map { @$_ } (values %{{ $rsrc->unique_constraints }} ) ) ) {
- my @pcols = $rsrc->primary_columns;
+ my @pcols = $rsrc->_pri_cols;
my $cursor = $shift_rs->search ({}, { order_by => { "-$ord", $position_column }, columns => \@pcols } )->cursor;
my $rs = $self->result_source->resultset;
- while (my @pks = $cursor->next ) {
-
+ my @all_pks = $cursor->all;
+ while (my $pks = shift @all_pks) {
my $cond;
for my $i (0.. $#pcols) {
- $cond->{$pcols[$i]} = $pks[$i];
+ $cond->{$pcols[$i]} = $pks->[$i];
}
$rs->search($cond)->update ({ $position_column => \ "$position_column $op 1" } );
);
}
+=head2 _position
+
+ my $num_pos = $item->_position;
+
+Returns the B<absolute numeric position> of the current object, with the
+first object being at position 1, its sibling at position 2 and so on.
+
+=cut
+sub _position {
+ my $self = shift;
+ return $self->_position_from_value ($self->get_column ($self->position_column) );
+}
+
=head2 _grouping_clause
This method returns one or more name=>value pairs for limiting a search
triggering any of the positioning integrity code).
Some day you might get confronted by datasets that have ambiguous
-positioning data (i.e. duplicate position values within the same group,
+positioning data (e.g. duplicate position values within the same group,
in a table without unique constraints). When manually fixing such data
keep in mind that you can not invoke L<DBIx::Class::Row/update> like
you normally would, as it will get confused by the wrong data before
=head1 CAVEATS
+=head2 Resultset Methods
+
+Note that all Insert/Create/Delete overrides are happening on
+L<DBIx::Class::Row> methods only. If you use the
+L<DBIx::Class::ResultSet> versions of
+L<update|DBIx::Class::ResultSet/update> or
+L<delete|DBIx::Class::ResultSet/delete>, all logic present in this
+module will be bypassed entirely (possibly resulting in a broken
+order-tree). Instead always use the
+L<update_all|DBIx::Class::ResultSet/update_all> and
+L<delete_all|DBIx::Class::ResultSet/delete_all> methods, which will
+invoke the corresponding L<row|DBIx::Class::Row> method on every
+member of the given resultset.
+
=head2 Race Condition on Insert
-If a position is not specified for an insert than a position
+If a position is not specified for an insert, a position
will be chosen based either on L</_initial_position_value> or
L</_next_position_value>, depending if there are already some
items in the current group. The space of time between the
=head2 Multiple Moves
-Be careful when issueing move_* methods to multiple objects. If
+Be careful when issuing move_* methods to multiple objects. If
you've pre-loaded the objects then when you move one of the objects
the position of the other object will not reflect their new value
until you reload them from the database - see
L<DBIx::Class::Row/discard_changes>.
There are times when you will want to move objects as groups, such
-as changeing the parent of several objects at once - this directly
+as changing the parent of several objects at once - this directly
conflicts with this problem. One solution is for us to write a
ResultSet class that supports a parent() method, for example. Another
solution is to somehow automagically modify the objects that exist
projects / dbsrgits/DBIx-Class.git / blobdiff