X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FStorage%2FDBI%2FCursor.pm;h=c9dedf652d127640448d4dd1301fcb6ede29ed3c;hb=a71859b4494bebdf765903546d332f9f3f805810;hp=87b0267102bccf5f9fe7e277cd5326a96cb0afff;hpb=28927b50e8ea9dbdf08a3ffeb9f1701f7b9fb99a;p=dbsrgits%2FDBIx-Class-Historic.git diff --git a/lib/DBIx/Class/Storage/DBI/Cursor.pm b/lib/DBIx/Class/Storage/DBI/Cursor.pm index 87b0267..c9dedf6 100644 --- a/lib/DBIx/Class/Storage/DBI/Cursor.pm +++ b/lib/DBIx/Class/Storage/DBI/Cursor.pm @@ -5,45 +5,165 @@ use base qw/DBIx::Class::Cursor/; use strict; use warnings; +=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 = $cursor->next; + +=head1 DESCRIPTION + +A Cursor represents a query cursor on a L object. It +allows for traversing the result set with L, retrieving all results with +L and resetting the cursor with L. + +Usually, you would use the cursor methods built into L +to traverse it. See L, +L and L for more +information. + +=head1 METHODS + +=head2 new + +Returns a new L object. + +=cut + sub new { - my ($it_class, $sth, $args, $attrs) = @_; + my ($class, $storage, $args, $attrs) = @_; #use Data::Dumper; warn Dumper(@_); - $it_class = ref $it_class if ref $it_class; + $class = ref $class if ref $class; my $new = { - sth => $sth, + storage => $storage, args => $args, pos => 0, - attrs => $attrs }; - return bless ($new, $it_class); + attrs => $attrs, + _dbh_gen => $storage->{_dbh_gen}, + }; + + return bless ($new, $class); } -sub next { - my ($self) = @_; - return if $self->{attrs}{rows} - && $self->{pos} >= $self->{attrs}{rows}; # + $self->{attrs}{offset}); - unless ($self->{live_sth}) { - $self->{sth}->execute(@{$self->{args} || []}); - if (my $offset = $self->{attrs}{offset}) { - $self->{sth}->fetch for 1 .. $offset; +=head2 next + +=over 4 + +=item Arguments: none + +=item Return Value: \@row_columns + +=back + +Advances the cursor to the next row and returns an arrayref of column values. + +=cut + +sub _dbh_next { + my ($storage, $dbh, $self) = @_; + + $self->_check_dbh_gen; + if ($self->{attrs}{rows} && $self->{pos} >= $self->{attrs}{rows}) { + $self->{sth}->finish if $self->{sth}->{Active}; + delete $self->{sth}; + $self->{done} = 1; + } + return if $self->{done}; + unless ($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->{live_sth} = 1; } my @row = $self->{sth}->fetchrow_array; - $self->{pos}++ if @row; + if (@row) { + $self->{pos}++; + } else { + delete $self->{sth}; + $self->{done} = 1; + } return @row; } -sub reset { +sub next { my ($self) = @_; + $self->{storage}->dbh_do($self->can('_dbh_next'), $self); +} + +=head2 all + +=over 4 + +=item Arguments: none + +=item Return Value: \@row_columns+ + +=back + +Returns a list of arrayrefs of column values for all rows in the +L. + +=cut + +sub _dbh_all { + my ($storage, $dbh, $self) = @_; + + $self->_check_dbh_gen; $self->{sth}->finish if $self->{sth}->{Active}; + delete $self->{sth}; + my ($rv, $sth) = $storage->_select(@{$self->{args}}); + return @{$sth->fetchall_arrayref}; +} + +sub all { + my ($self) = @_; + return $self->SUPER::all if $self->{attrs}{rows}; + $self->{storage}->dbh_do($self->can('_dbh_all'), $self); +} + +=head2 reset + +Resets the cursor to the beginning of the L. + +=cut + +sub reset { + my ($self) = @_; + + # No need to care about failures here + eval { $self->{sth}->finish if $self->{sth} && $self->{sth}->{Active} }; + $self->_soft_reset; +} + +sub _soft_reset { + my ($self) = @_; + + delete $self->{sth}; + delete $self->{done}; $self->{pos} = 0; - $self->{live_sth} = 0; return $self; } +sub _check_dbh_gen { + my ($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 + eval { $self->{sth}->finish if $self->{sth} && $self->{sth}->{Active} }; } 1;