use warnings;
use base qw/DBIx::Class::Storage::DBI::MSSQL/;
+use mro 'c3';
-sub _prep_for_execute {
+use Carp::Clan qw/^DBIx::Class/;
+use List::Util();
+use Scalar::Util ();
+
+__PACKAGE__->mk_group_accessors(simple => qw/
+ _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. It is
+loaded automatically by by DBIx::Class::Storage::DBI::ODBC when it detects a
+MSSQL back-end.
+
+Most of the functionality is provided from the superclass
+L<DBIx::Class::Storage::DBI::MSSQL>.
+
+=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.
+
+Alternatively, you can add it yourself and dynamic cursor support will be
+automatically enabled.
+
+If you're using FreeTDS, C<tds_version> must be set to at least C<8.0>.
+
+This will not work with CODE ref connect_info's.
+
+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 = $self->_dbi_connect_info->[-1];
+
+ unless (ref($dbi_attrs) && Scalar::Util::reftype($dbi_attrs) eq 'HASH') {
+ $dbi_attrs = {};
+ push @{ $self->_dbi_connect_info }, $dbi_attrs;
+ }
+
+ if (not exists $dbi_attrs->{odbc_cursortype}) {
+ # turn on support for multiple concurrent statements, unless overridden
+ $dbi_attrs->{odbc_cursortype} = 2;
+ $self->disconnect; # resetting dbi attrs, so have to reconnect
+ $self->ensure_connected;
+ $self->_set_dynamic_cursors;
+ }
+}
+
+sub _set_dynamic_cursors {
my $self = shift;
- my ($op, $extra_bind, $ident, $args) = @_;
-
- my ($sql, $bind) = $self->next::method (@_);
- $sql .= ';SELECT SCOPE_IDENTITY()' if $op eq 'insert';
-
- my $alias2src = $self->_resolve_ident_sources($ident);
- my %identity_insert_tables;
- foreach my $bound (@{$bind}) {
- my $col = $bound->[0];
- my $name_sep = $self->_sql_maker_opts->{name_sep} || '.';
-
- $col =~ s/^([^\Q${name_sep}\E]*)\Q${name_sep}\E//;
- my $alias = $1 || 'me';
- my $rsrc = $alias2src->{$alias};
-
- my $is_auto_increment = $rsrc && $rsrc->column_info($col)->{is_auto_increment};
- my $table;
- if ($is_auto_increment) {
- $identity_insert_tables{$rsrc->from} = 1;
- }
+ my $dbh = $self->_get_dbh;
+
+ eval {
+ local $dbh->{RaiseError} = 1;
+ local $dbh->{PrintError} = 0;
+ $dbh->do('SELECT @@IDENTITY');
+ };
+ if ($@) {
+ croak <<'EOF';
+
+Your drivers do not seem to support dynamic cursors (odbc_cursortype => 2),
+if you're using FreeTDS, make sure to set tds_version to 8.0 or greater.
+EOF
}
- my $identity_insert_on = join '', map { "SET IDENTITY_INSERT $_ ON; " } keys %identity_insert_tables;
- my $identity_insert_off = join '', map { "SET IDENTITY_INSERT $_ OFF; " } keys %identity_insert_tables;
- $sql = "$identity_insert_on $sql $identity_insert_off";
+ $self->_using_dynamic_cursors(1);
+ $self->_identity_method('@@identity');
+}
+
+sub _rebless {
+ no warnings 'uninitialized';
+ my $self = shift;
- return ($sql, $bind);
+ if (ref($self->_dbi_connect_info->[0]) ne 'CODE' &&
+ eval { $self->_dbi_connect_info->[-1]{odbc_cursortype} } == 2) {
+ $self->_set_dynamic_cursors;
+ return;
+ }
+
+ $self->_using_dynamic_cursors(0);
}
-sub _execute {
- my $self = shift;
- my ($op) = @_;
+=head2 connect_call_use_server_cursors
+
+Use as:
+
+ on_connect_call => 'use_server_cursors'
- my ($rv, $sth, @bind) = $self->dbh_do($self->can('_dbh_execute'), @_);
- if ($op eq 'insert') {
- $self->{_scope_identity} = $sth->fetchrow_array;
- $sth->finish;
- }
+May allow multiple active select statements. See
+L<DBD::ODBC/odbc_SQL_ROWSET_SIZE> for more information.
- return wantarray ? ($rv, $sth, @bind) : $rv;
+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
+
+sub connect_call_use_server_cursors {
+ my $self = shift;
+ my $sql_rowset_size = shift || 2;
+
+ $self->_get_dbh->{odbc_SQL_ROWSET_SIZE} = $sql_rowset_size;
}
-sub last_insert_id { shift->{_scope_identity} }
+=head2 connect_call_use_MARS
-1;
+Use as:
-__END__
+ on_connect_call => 'use_MARS'
-=head1 NAME
+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.
-DBIx::Class::Storage::DBI::ODBC::Microsoft_SQL_Server - Support specific
-to Microsoft SQL Server over ODBC
+B<WARNING>: This has implications for the way transactions are handled.
-=head1 DESCRIPTION
+=cut
-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.
+sub connect_call_use_MARS {
+ my $self = shift;
-=head1 IMPLEMENTATION NOTES
+ my $dsn = $self->_dbi_connect_info->[0];
-Microsoft SQL Server supports three methods of retrieving the IDENTITY
-value for inserted row: IDENT_CURRENT, @@IDENTITY, and SCOPE_IDENTITY().
-SCOPE_IDENTITY is used here because it is the safest. However, it must
-be called is the same execute statement, not just the same connection.
+ if (ref($dsn) eq 'CODE') {
+ croak 'cannot change the DBI DSN on a CODE ref connect_info';
+ }
-So, this implementation appends a SELECT SCOPE_IDENTITY() statement
-onto each INSERT to accommodate that requirement.
+ if ($dsn !~ /MARS_Connection=/) {
+ $self->_dbi_connect_info->[0] = "$dsn;MARS_Connection=Yes";
+ my $was_connected = defined $self->_dbh;
+ $self->disconnect;
+ $self->ensure_connected if $was_connected;
+ }
+}
+
+1;
-=head1 AUTHORS
+=head1 AUTHOR
-Marc Mims C<< <marc@questright.com> >>
+See L<DBIx::Class/CONTRIBUTORS>.
=head1 LICENSE