package DBIx::Class::Storage::DBI::Cursor;
-use base qw/DBIx::Class::Cursor/;
-
use strict;
use warnings;
+use base qw/DBIx::Class::Cursor/;
+
+__PACKAGE__->mk_group_accessors('simple' =>
+ qw/sth/
+);
+
+=head1 NAME
+
+DBIx::Class::Storage::DBI::Cursor - Object representing a query cursor on a
+resultset.
+
+=head1 SYNOPSIS
+
+ my $cursor = $schema->resultset('CD')->cursor();
+ my $first_cd = $cursor->next;
+
+=head1 DESCRIPTION
+
+A Cursor represents a query cursor on a L<DBIx::Class::ResultSet> object. It
+allows for traversing the result set with L</next>, retrieving all results with
+L</all> and resetting the cursor with L</reset>.
+
+Usually, you would use the cursor methods built into L<DBIx::Class::ResultSet>
+to traverse it. See L<DBIx::Class::ResultSet/next>,
+L<DBIx::Class::ResultSet/reset> and L<DBIx::Class::ResultSet/all> for more
+information.
+
+=head1 METHODS
+
+=head2 new
+
+Returns a new L<DBIx::Class::Storage::DBI::Cursor> object.
+
+=cut
+
sub new {
my ($class, $storage, $args, $attrs) = @_;
- #use Data::Dumper; warn Dumper(@_);
$class = ref $class if ref $class;
+
my $new = {
storage => $storage,
args => $args,
pos => 0,
- attrs => $attrs };
+ attrs => $attrs,
+ _dbh_gen => $storage->{_dbh_gen},
+ };
+
return bless ($new, $class);
}
-sub next {
- my ($self) = @_;
- if ($self->{attrs}{rows} && $self->{pos} >= $self->{attrs}{rows}) {
- $self->{sth}->finish if $self->{sth}->{Active};
- delete $self->{sth};
+=head2 next
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: \@row_columns
+
+=back
+
+Advances the cursor to the next row and returns an array of column
+values (the result of L<DBI/fetchrow_array> method).
+
+=cut
+
+sub _dbh_next {
+ my ($storage, $dbh, $self) = @_;
+
+ $self->_check_dbh_gen;
+ if (
+ $self->{attrs}{software_limit}
+ && $self->{attrs}{rows}
+ && $self->{pos} >= $self->{attrs}{rows}
+ ) {
+ $self->sth->finish if $self->sth->{Active};
+ $self->sth(undef);
$self->{done} = 1;
}
return if $self->{done};
- unless ($self->{sth}) {
- $self->{sth} = ($self->{storage}->_select(@{$self->{args}}))[1];
+ unless ($self->sth) {
+ $self->sth(($storage->_select(@{$self->{args}}))[1]);
if ($self->{attrs}{software_limit}) {
if (my $offset = $self->{attrs}{offset}) {
- $self->{sth}->fetch for 1 .. $offset;
+ $self->sth->fetch for 1 .. $offset;
}
}
}
- my @row = $self->{sth}->fetchrow_array;
+ my @row = $self->sth->fetchrow_array;
if (@row) {
$self->{pos}++;
} else {
- delete $self->{sth};
+ $self->sth(undef);
$self->{done} = 1;
}
return @row;
}
-sub all {
+sub next {
my ($self) = @_;
- return $self->SUPER::all if $self->{attrs}{rows};
- $self->{sth}->finish if $self->{sth}->{Active};
- delete $self->{sth};
- my ($rv, $sth) = $self->{storage}->_select(@{$self->{args}});
+ $self->{storage}->dbh_do($self->can('_dbh_next'), $self);
+}
+
+=head2 all
+
+=over 4
+
+=item Arguments: none
+
+=item Return Value: \@row_columns+
+
+=back
+
+Returns a list of arrayrefs of column values for all rows in the
+L<DBIx::Class::ResultSet>.
+
+=cut
+
+sub _dbh_all {
+ my ($storage, $dbh, $self) = @_;
+
+ $self->_check_dbh_gen;
+ $self->sth->finish if $self->sth && $self->sth->{Active};
+ $self->sth(undef);
+ my ($rv, $sth) = $storage->_select(@{$self->{args}});
return @{$sth->fetchall_arrayref};
}
+sub all {
+ my ($self) = @_;
+ if ($self->{attrs}{software_limit}
+ && ($self->{attrs}{offset} || $self->{attrs}{rows})) {
+ return $self->next::method;
+ }
+
+ $self->{storage}->dbh_do($self->can('_dbh_all'), $self);
+}
+
+=head2 reset
+
+Resets the cursor to the beginning of the L<DBIx::Class::ResultSet>.
+
+=cut
+
sub reset {
my ($self) = @_;
- $self->{sth}->finish if $self->{sth}->{Active};
- delete $self->{sth};
- $self->{pos} = 0;
+
+ # No need to care about failures here
+ eval { $self->sth->finish if $self->sth && $self->sth->{Active} };
+ $self->_soft_reset;
+ return undef;
+}
+
+sub _soft_reset {
+ my ($self) = @_;
+
+ $self->sth(undef);
delete $self->{done};
- return $self;
+ $self->{pos} = 0;
+}
+
+sub _check_dbh_gen {
+ my ($self) = @_;
+
+ if($self->{_dbh_gen} != $self->{storage}->{_dbh_gen}) {
+ $self->{_dbh_gen} = $self->{storage}->{_dbh_gen};
+ $self->_soft_reset;
+ }
}
sub DESTROY {
my ($self) = @_;
- $self->{sth}->finish if $self->{sth}->{Active};
+
+ # None of the reasons this would die matter if we're in DESTROY anyways
+ local $@;
+ eval { $self->sth->finish if $self->sth && $self->sth->{Active} };
}
1;