use strict;
use warnings;
-use base qw/DBIx::Class::Storage::DBI::MSSQL/;
+use base qw/
+ DBIx::Class::Storage::DBI::ODBC
+ DBIx::Class::Storage::DBI::MSSQL
+/;
use mro 'c3';
-
-use Carp::Clan qw/^DBIx::Class/;
-use List::Util();
-use Scalar::Util ();
+use Scalar::Util 'reftype';
+use Try::Tiny;
+use DBIx::Class::Carp;
+use namespace::clean;
__PACKAGE__->mk_group_accessors(simple => qw/
_using_dynamic_cursors
=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
+loaded automatically 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 USAGE NOTES
+
+=head2 Basic Linux Setup (Debian)
+
+ sudo aptitude install tdsodbc libdbd-odbc-perl unixodbc
+
+In case it is not already there put the following (adjust for non-64bit arch) in
+C</etc/odbcinst.ini>:
+
+ [FreeTDS]
+ Description = FreeTDS
+ Driver = /usr/lib/x86_64-linux-gnu/odbc/libtdsodbc.so
+ Setup = /usr/lib/x86_64-linux-gnu/odbc/libtdsS.so
+ UsageCount = 1
+
+Set your C<$dsn> in L<connect_info|DBIx::Class::Storage::DBI/connect_info> as follows:
+
+ dbi:ODBC:server=<my.host.name>;port=1433;driver=FreeTDS;tds_version=8.0
+
+If you use the EasySoft driver (L<http://www.easysoft.com>):
+
+ dbi:ODBC:server=<my.host.name>;port=1433;driver=Easysoft ODBC-SQL Server
+
+=head2 Basic Windows Setup
+
+Use the following C<$dsn> for the Microsoft ODBC driver:
+
+ dbi:ODBC:driver={SQL Server};server=SERVER\SQL_SERVER_INSTANCE_NAME
+
+And for the Native Client:
+
+ dbi:ODBC:driver={SQL Server Native Client 10.0};server=SERVER\SQL_SERVER_INSTANCE_NAME
+
+Go into Control Panel -> System and Security -> Administrative Tools -> Data
+Sources (ODBC) to check driver names and to set up data sources.
+
+Use System DSNs, not User DSNs if you want to use DSNs.
+
+If you set up a DSN, use the following C<$dsn> for
+L<connect_info|DBIx::Class::Storage::DBI/connect_info>:
+
+ dbi:ODBC:dsn=MY_DSN
+
=head1 MULTIPLE ACTIVE STATEMENTS
The following options are alternative ways to enable concurrent executing
-statement support. Each has its own advantages and drawbacks.
+statement support. Each has its own advantages and drawbacks and works on
+different platforms. Read each section carefully.
+
+For more details about using MAS in MSSQL over DBD::ODBC see this excellent
+document provided by EasySoft:
+L<http://www.easysoft.com/developer/languages/perl/multiple-active-statements.html>.
+
+In order of preference, they are:
+
+=over 8
+
+=item * L<mars|/connect_call_use_mars>
+
+=item * L<dynamic_cursors|/connect_call_use_dynamic_cursors>
+
+=item * L<server_cursors|/connect_call_use_server_cursors>
+
+=back
+
+=head1 METHODS
+
+=head2 connect_call_use_mars
+
+Use as:
+
+ on_connect_call => 'use_mars'
+
+in your connection info, or alternatively specify it directly:
+
+ Your::Schema->connect (
+ $original_dsn . '; MARS_Connection=Yes',
+ $user,
+ $pass,
+ \%attrs,
+ )
+
+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.
+
+This does not work on FreeTDS drivers at the time of this writing, and only
+works with the Native Client, later versions of the Windows MS ODBC driver, and
+the Easysoft driver.
+
+=cut
+
+sub connect_call_use_mars {
+ my $self = shift;
+
+ my $dsn = $self->_dbi_connect_info->[0];
+
+ if (ref($dsn) eq 'CODE') {
+ $self->throw_exception('cannot change the DBI DSN on a CODE ref connect_info');
+ }
+
+ if ($dsn !~ /MARS_Connection=/) {
+ if ($self->_using_freetds) {
+ $self->throw_exception('FreeTDS does not support MARS at the time of '
+ .'writing.');
+ }
+
+ if (exists $self->_server_info->{normalized_dbms_version} &&
+ $self->_server_info->{normalized_dbms_version} < 9) {
+ $self->throw_exception('SQL Server 2005 or later required to use MARS.');
+ }
+
+ if (my ($data_source) = $dsn =~ /^dbi:ODBC:([\w-]+)\z/i) { # prefix with DSN
+ carp_unique "Bare DSN in ODBC connect string, rewriting as 'dsn=$data_source'"
+ ." for MARS\n";
+ $dsn = "dbi:ODBC:dsn=$data_source";
+ }
+
+ $self->_dbi_connect_info->[0] = "$dsn;MARS_Connection=Yes";
+ $self->disconnect;
+ $self->ensure_connected;
+ }
+}
+
+sub connect_call_use_MARS {
+ carp "'connect_call_use_MARS' has been deprecated, use "
+ ."'connect_call_use_mars' instead.";
+ shift->connect_call_use_mars(@_)
+}
=head2 connect_call_use_dynamic_cursors
on_connect_call => 'use_dynamic_cursors'
-in your L<DBIx::Class::Storage::DBI/connect_info> as one way to enable multiple
-concurrent statements.
+Which will add C<< odbc_cursortype => 2 >> to your DBI connection
+attributes, or alternatively specify the necessary flag directly:
-Will add C<< odbc_cursortype => 2 >> to your DBI connection attributes. See
-L<DBD::ODBC/odbc_cursortype> for more information.
+ Your::Schema->connect (@dsn, { ... odbc_cursortype => 2 })
-Alternatively, you can add it yourself and dynamic cursor support will be
-automatically enabled.
+See L<DBD::ODBC/odbc_cursortype> for more information.
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.
+B<WARNING:> on FreeTDS (and maybe some other drivers) 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.
+
+B<WARNING:> on FreeTDS, changes made in one statement (e.g. an insert) may not
+be visible from a following statement (e.g. a select.)
+
+B<WARNING:> FreeTDS versions > 0.82 seem to have completely broken the ODBC
+protocol. DBIC will not allow dynamic cursor support with such versions to
+protect your data. Please hassle the authors of FreeTDS to act on the bugs that
+make their driver not overly usable with DBD::ODBC.
=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';
- }
+ if (($self->_dbic_connect_attributes->{odbc_cursortype} || 0) < 2) {
- my $dbi_attrs = $self->_dbi_connect_info->[-1];
+ my $dbi_inf = $self->_dbi_connect_info;
- unless (ref($dbi_attrs) && Scalar::Util::reftype($dbi_attrs) eq 'HASH') {
- $dbi_attrs = {};
- push @{ $self->_dbi_connect_info }, $dbi_attrs;
- }
+ $self->throw_exception ('Cannot set DBI attributes on a CODE ref connect_info')
+ if ref($dbi_inf->[0]) eq 'CODE';
- if (not exists $dbi_attrs->{odbc_cursortype}) {
- # turn on support for multiple concurrent statements, unless overridden
- $dbi_attrs->{odbc_cursortype} = 2;
- my $connected = defined $self->_dbh;
- $self->disconnect;
- $self->ensure_connected if $connected;
- $self->_set_dynamic_cursors;
- }
-}
+ # reenter connection information with the attribute re-set
+ $dbi_inf->[3] = {} if @$dbi_inf <= 3;
+ $dbi_inf->[3]{odbc_cursortype} = 2;
-sub _set_dynamic_cursors {
- my $self = shift;
- my $dbh = $self->_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
- }
+ $self->_dbi_connect_info($dbi_inf);
- $self->_using_dynamic_cursors(1);
- $self->_identity_method('@@identity');
+ $self->disconnect; # resetting dbi attrs, so have to reconnect
+ $self->ensure_connected;
+ }
}
-sub _rebless {
- no warnings 'uninitialized';
+sub _run_connection_actions {
my $self = shift;
- if (ref($self->_dbi_connect_info->[0]) ne 'CODE' &&
- eval { $self->_dbi_connect_info->[-1]{odbc_cursortype} } == 2) {
- $self->_set_dynamic_cursors;
- return;
+ $self->next::method (@_);
+
+ # keep the dynamic_cursors_support and driver-state in sync
+ # on every reconnect
+ my $use_dyncursors = ($self->_dbic_connect_attributes->{odbc_cursortype} || 0) > 1;
+ if (
+ $use_dyncursors
+ xor
+ !!$self->_using_dynamic_cursors
+ ) {
+ if ($use_dyncursors) {
+ try {
+ my $dbh = $self->_dbh;
+ local $dbh->{RaiseError} = 1;
+ local $dbh->{PrintError} = 0;
+ $dbh->do('SELECT @@IDENTITY');
+ } catch {
+ $self->throw_exception (
+ 'Your drivers do not seem to support dynamic cursors (odbc_cursortype => 2).'
+ . (
+ $self->_using_freetds
+ ? ' If you are using FreeTDS, make sure to set tds_version to 8.0 or greater.'
+ : ''
+ )
+ );
+ };
+
+ $self->_using_dynamic_cursors(1);
+ $self->_identity_method('@@identity');
+ }
+ else {
+ $self->_using_dynamic_cursors(0);
+ $self->_identity_method(undef);
+ }
}
- $self->_using_dynamic_cursors(0);
+ $self->_no_scope_identity_query($self->_using_dynamic_cursors
+ ? $self->_using_freetds
+ : undef
+ );
+
+ # freetds is too damn broken, some fixups
+ if ($self->_using_freetds) {
+
+ # no dynamic cursors starting from 0.83
+ if ($self->_using_dynamic_cursors) {
+ my $fv = $self->_using_freetds_version || 999; # assume large if can't be determined
+ $self->throw_exception(
+ 'Dynamic cursors (odbc_cursortype => 2) are not supported with FreeTDS > 0.82 '
+ . "(you have $fv). Please hassle FreeTDS authors to fix the outstanding bugs in "
+ . 'their driver.'
+ ) if $fv > 0.82
+ }
+
+ # FreeTDS is too broken wrt execute_for_fetch batching
+ # just disable it outright until things quiet down
+ $self->_disable_odbc_array_ops;
+ }
}
=head2 connect_call_use_server_cursors
B<WARNING>: this does not work on all versions of SQL Server, and may lock up
your database!
+At the time of writing, this option only works on Microsoft's Windows drivers,
+later versions of the ODBC driver and the Native Client driver.
+
=cut
sub connect_call_use_server_cursors {
my $self = shift;
my $sql_rowset_size = shift || 2;
+ if ($^O !~ /win32|cygwin/i) {
+ $self->throw_exception('Server cursors only work on Windows platforms at '
+ .'the time of writing.');
+ }
+
$self->_get_dbh->{odbc_SQL_ROWSET_SIZE} = $sql_rowset_size;
}
-=head2 connect_call_use_MARS
+=head1 FURTHER QUESTIONS?
-Use as:
+Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
- on_connect_call => 'use_MARS'
+=head1 COPYRIGHT AND LICENSE
-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.
+This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
+by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
+redistribute it and/or modify it under the same terms as the
+L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.
=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 $was_connected = defined $self->_dbh;
- $self->disconnect;
- $self->ensure_connected if $was_connected;
- }
-}
-
1;
-=head1 AUTHOR
-
-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
+# vim:sw=2 sts=2 et
projects / dbsrgits/DBIx-Class.git / blobdiff