document placeholders_with_type_conversion_supported and add a redispatch to reblesse...

[dbsrgits/DBIx-Class.git] / lib / DBIx / Class / Storage / DBI / Sybase / Base.pm

package DBIx::Class::Storage::DBI::Sybase::Base;

use strict;
use warnings;

use base qw/DBIx::Class::Storage::DBI/;
use mro 'c3';

=head1 NAME

DBIx::Class::Storage::DBI::Sybase::Base - Common functionality for drivers using
DBD::Sybase

=head1 DESCRIPTION

This is the base class for L<DBIx::Class::Storage::DBI::Sybase> and
L<DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server>. It provides some
utility methods related to L<DBD::Sybase> and the supported functions of the
database you are connecting to.

=head1 METHODS

=cut

sub _ping {
  my $self = shift;

  my $dbh = $self->_dbh or return 0;

  local $dbh->{RaiseError} = 1;
  eval {
    $dbh->do('select 1');
  };

  return $@ ? 0 : 1;
}

=head2 placeholders_supported

Whether or not string placeholders work. Does not check for implicit conversion
errors, see L</placeholders_with_type_conversion_supported>.

=cut

sub placeholders_supported {
  my $self = shift;
  my $dbh  = $self->last_dbh;

  return eval {
# There's also $dbh->{syb_dynamic_supported} but it can be inaccurate for this
# purpose.
    local $dbh->{PrintError} = 0;
    local $dbh->{RaiseError} = 1;
    $dbh->selectrow_array('select ?', {}, 1);
  };
}

=head2 placeholders_with_type_conversion_supported 

Checks if placeholders bound to non-string types throw implicit type conversion
errors or not.

See L<DBIx::Class::Storage::DBI::Sybase/connect_call_set_auto_cast>.

=cut

sub placeholders_with_type_conversion_supported {
  my $self = shift;
  my $dbh  = $self->_dbh;

  return eval {
    local $dbh->{PrintError} = 0;
    local $dbh->{RaiseError} = 1;
# this specifically tests a bind that is NOT a string
    $dbh->selectrow_array('select 1 where 1 = ?', {}, 1);
  };
}

sub _set_max_connect {
  my $self = shift;
  my $val  = shift || 256;

  my $dsn = $self->_dbi_connect_info->[0];

  return if ref($dsn) eq 'CODE';

  if ($dsn !~ /maxConnect=/) {
    $self->_dbi_connect_info->[0] = "$dsn;maxConnect=$val";
    my $connected = defined $self->_dbh;
    $self->disconnect;
    $self->ensure_connected if $connected;
  }
}

=head2 using_freetds

Whether or not L<DBD::Sybase> was compiled against FreeTDS. If false, it means
the Sybase OpenClient libraries were used.

=cut

sub using_freetds {
  my $self = shift;

  return $self->_dbh->{syb_oc_version} =~ /freetds/i;
}

=head2 set_textsize

When using FreeTDS and/or MSSQL, C<< $dbh->{LongReadLen} >> is not available,
use this function instead. It does:

  $dbh->do("SET TEXTSIZE $bytes");

Takes the number of bytes, or uses the C<LongReadLen> value from your
L<DBIx::Class/connect_info> if omitted.

=cut

sub set_textsize {
  my $self = shift;
  my $text_size = shift ||
    eval { $self->_dbi_connect_info->[-1]->{LongReadLen} };

  return unless defined $text_size;

  $self->_dbh->do("SET TEXTSIZE $text_size");
}

1;

=head1 AUTHORS

See L<DBIx::Class/CONTRIBUTORS>.

=head1 LICENSE

You may distribute this code under the same terms as Perl itself.

=cut