X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FStorage%2FDBI%2FODBC%2FMicrosoft_SQL_Server.pm;h=f263fb3ebdb7f99484fa0513bd269cc4b08e4f4f;hb=7f32c82b6791c30615bd6da46063e2a80be3ebc5;hp=2fde285e75d671bd77eccba1f20c5ab52f37acbd;hpb=2ad62d97476187e57d20ee49b39d7a7af864bb20;p=dbsrgits%2FDBIx-Class.git

diff --git a/lib/DBIx/Class/Storage/DBI/ODBC/Microsoft_SQL_Server.pm b/lib/DBIx/Class/Storage/DBI/ODBC/Microsoft_SQL_Server.pm
index 2fde285..f263fb3 100644
--- a/lib/DBIx/Class/Storage/DBI/ODBC/Microsoft_SQL_Server.pm
+++ b/lib/DBIx/Class/Storage/DBI/ODBC/Microsoft_SQL_Server.pm
@@ -4,9 +4,147 @@ use warnings;
 
 use base qw/DBIx::Class::Storage::DBI::MSSQL/;
 use mro 'c3';
-
+use Carp::Clan qw/^DBIx::Class/;
 use List::Util();
 
+__PACKAGE__->mk_group_accessors(simple => qw/
+  _identity _using_dynamic_cursors
+/);
+
+=head1 NAME
+
+DBIx::Class::Storage::DBI::ODBC::Microsoft_SQL_Server - Support specific
+to Microsoft SQL Server over ODBC
+
+=head1 DESCRIPTION
+
+This class implements support specific to Microsoft SQL Server over ODBC,
+including auto-increment primary keys and SQL::Abstract::Limit dialect.  It
+is loaded automatically by by DBIx::Class::Storage::DBI::ODBC when it
+detects a MSSQL back-end.
+
+=head1 IMPLEMENTATION NOTES
+
+Microsoft SQL Server supports three methods of retrieving the C<IDENTITY>
+value for inserted row: C<IDENT_CURRENT>, C<@@IDENTITY>, and C<SCOPE_IDENTITY()>.
+C<SCOPE_IDENTITY()> is used here because it is the safest.  However, it must
+be called is the same execute statement, not just the same connection.
+
+So, this implementation appends a C<SELECT SCOPE_IDENTITY()> statement
+onto each C<INSERT> to accommodate that requirement.
+
+If you use dynamic cursors with C<< odbc_cursortype => 2 >> or
+L</on_connect_call_use_dynamic_cursors> then the less accurate
+C<SELECT @@IDENTITY> is used instead.
+
+=head1 MULTIPLE ACTIVE STATEMENTS
+
+The following options are alternative ways to enable concurrent executing
+statement support. Each has its own advantages and drawbacks.
+
+=head2 connect_call_use_dynamic_cursors
+
+Use as:
+
+  on_connect_call => 'use_dynamic_cursors'
+
+in your L<DBIx::Class::Storage::DBI/connect_info> as one way to enable multiple
+concurrent statements.
+
+Will add C<< odbc_cursortype => 2 >> to your DBI connection attributes. See
+L<DBD::ODBC/odbc_cursortype> for more information.
+
+This will not work with CODE ref connect_info's and will do nothing if you set
+C<odbc_cursortype> yourself.
+
+B<WARNING:> this will break C<SCOPE_IDENTITY()>, and C<SELECT @@IDENTITY> will
+be used instead, which on SQL Server 2005 and later will return erroneous
+results on tables which have an on insert trigger that inserts into another
+table with an C<IDENTITY> column.
+
+=cut
+
+sub connect_call_use_dynamic_cursors {
+  my $self = shift;
+
+  if (ref($self->_dbi_connect_info->[0]) eq 'CODE') {
+    croak 'cannot set DBI attributes on a CODE ref connect_info';
+  }
+
+  my $dbi_attrs = $self->_dbi_connect_info->[-1];
+  $dbi_attrs ||= {};
+
+  if (not exists $dbi_attrs->{odbc_cursortype}) {
+    # turn on support for multiple concurrent statements, unless overridden
+    $self->_dbi_connect_info->[-1] = { %$dbi_attrs, odbc_cursortype => 2 };
+    my $connected = defined $self->_dbh;
+    $self->disconnect;
+    $self->ensure_connected if $connected;
+    $self->_using_dynamic_cursors(1);
+  }
+}
+
+sub _rebless {
+  no warnings 'uninitialized';
+  my $self = shift;
+
+  if (ref($self->_dbi_connect_info->[0]) ne 'CODE' &&
+      $self->_dbi_connect_info->[-1]{odbc_cursortype} == 2) {
+    $self->_using_dynamic_cursors(1);
+    return;
+  }
+
+  $self->_using_dynamic_cursors(0);
+}
+
+=head2 connect_call_use_server_cursors
+
+Use as:
+
+  on_connect_call => 'use_server_cursors'
+
+May allow multiple active select statements. See
+L<DBD::ODBC/odbc_SQL_ROWSET_SIZE> for more information.
+
+Takes an optional parameter for the value to set the attribute to, default is
+C<2>.
+
+B<WARNING>: this does not work on all versions of SQL Server, and may lock up
+your database!
+
+=cut
+
+=head2 connect_call_use_mars
+
+Use as:
+
+  on_connect_call => 'use_mars'
+
+Use to enable a feature of SQL Server 2005 and later, "Multiple Active Result
+Sets". See L<DBD::ODBC::FAQ/Does DBD::ODBC support Multiple Active Statements?>
+for more information.
+
+B<WARNING>: This has implications for the way transactions are handled.
+
+=cut
+
+sub connect_call_use_mars {
+  my $self = shift;
+
+  my $dsn = $self->_dbi_connect_info->[0];
+
+  if (ref($dsn) eq 'CODE') {
+    croak 'cannot change the DBI DSN on a CODE ref connect_info';
+  }
+
+  if ($dsn !~ /MARS_Connection=/) {
+    $self->_dbi_connect_info->[0] = "$dsn;MARS_Connection=Yes";
+    my $connected = defined $self->_dbh;
+    $self->disconnect;
+    $self->ensure_connected if $connected;
+  }
+}
+
 sub insert_bulk {
   my $self = shift;
   my ($source, $cols, $data) = @_;
@@ -23,14 +161,14 @@ sub insert_bulk {
 
   if ($identity_insert) {
     my $table = $source->from;
-    $self->dbh->do("SET IDENTITY_INSERT $table ON");
+    $self->_get_dbh->do("SET IDENTITY_INSERT $table ON");
   }
 
   $self->next::method(@_);
 
   if ($identity_insert) {
     my $table = $source->from;
-    $self->dbh->do("SET IDENTITY_INSERT $table OFF");
+    $self->_get_dbh->do("SET IDENTITY_INSERT $table OFF");
   }
 }
 
@@ -62,48 +200,31 @@ sub _execute {
 
     my ($rv, $sth, @bind) = $self->dbh_do($self->can('_dbh_execute'), @_);
     if ($op eq 'insert') {
-      $self->{_scope_identity} = $sth->fetchrow_array;
+      my ($identity) = $sth->fetchrow_array;
       $sth->finish;
+
+      if ((not defined $identity) && $self->_using_dynamic_cursors) {
+        ($identity) = $self->_dbh->selectrow_array('select @@identity');
+      }
+
+      $self->_identity($identity);
     }
 
     return wantarray ? ($rv, $sth, @bind) : $rv;
 }
 
-sub last_insert_id { shift->{_scope_identity} }
+sub last_insert_id { shift->_identity() }
 
 1;
 
-__END__
-
-=head1 NAME
-
-DBIx::Class::Storage::DBI::ODBC::Microsoft_SQL_Server - Support specific
-to Microsoft SQL Server over ODBC
-
-=head1 DESCRIPTION
-
-This class implements support specific to Microsoft SQL Server over ODBC,
-including auto-increment primary keys and SQL::Abstract::Limit dialect.  It
-is loaded automatically by by DBIx::Class::Storage::DBI::ODBC when it
-detects a MSSQL back-end.
+=head1 AUTHOR
 
-=head1 IMPLEMENTATION NOTES
-
-Microsoft SQL Server supports three methods of retrieving the IDENTITY
-value for inserted row: IDENT_CURRENT, @@IDENTITY, and SCOPE_IDENTITY().
-SCOPE_IDENTITY is used here because it is the safest.  However, it must
-be called is the same execute statement, not just the same connection.
-
-So, this implementation appends a SELECT SCOPE_IDENTITY() statement
-onto each INSERT to accommodate that requirement.
-
-=head1 AUTHORS
-
-Marc Mims C<< <marc@questright.com> >>
+See L<DBIx::Class/CONTRIBUTORS>.
 
 =head1 LICENSE
 
 You may distribute this code under the same terms as Perl itself.
 
 =cut
+
 # vim: sw=2 sts=2