From: Rafael Kitover Date: Fri, 24 Dec 2010 12:53:11 +0000 (+0100) Subject: Refactor/improve support of DBD::Sybase compiled against FreeTDS (mainly MSSQL) X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=c1e5a9ac6c284bd48bdef09379ff544ec7fb9629;p=dbsrgits%2FDBIx-Class-Historic.git Refactor/improve support of DBD::Sybase compiled against FreeTDS (mainly MSSQL) --- diff --git a/Changes b/Changes index 6a1c165..dc243b4 100644 --- a/Changes +++ b/Changes @@ -38,6 +38,8 @@ Revision history for DBIx::Class - Automatically require the requested cursor class before use (RT#64795) - Work around a Firebird ODBC driver bug exposed by DBD::ODBC 1.29 + - Fix (to the extent allowed by the driver) transaction support in + DBD::Sybase compiled against FreeTDS - Fix exiting via next warnings in ResultSource::sequence() - Fix stripping of table qualifiers in update/delete in arrayref condition elements diff --git a/lib/DBIx/Class/Storage/DBI/Sybase.pm b/lib/DBIx/Class/Storage/DBI/Sybase.pm index abf15bf..901cf0a 100644 --- a/lib/DBIx/Class/Storage/DBI/Sybase.pm +++ b/lib/DBIx/Class/Storage/DBI/Sybase.pm @@ -45,6 +45,31 @@ sub _rebless { } } +sub _init { + # once the driver is determined see if we need to insert the DBD::Sybase w/ FreeTDS fixups + # this is a dirty version of "instance role application", \o/ DO WANT Moo \o/ + my $self = shift; + if (! $self->isa('DBIx::Class::Storage::DBI::Sybase::FreeTDS') and $self->using_freetds) { + require DBIx::Class::Storage::DBI::Sybase::FreeTDS; + + my @isa = @{mro::get_linear_isa(ref $self)}; + my $class = shift @isa; # this is our current ref + + my $trait_class = $class . '::FreeTDS'; + mro::set_mro ($trait_class, 'c3'); + no strict 'refs'; + @{"${trait_class}::ISA"} = ($class, 'DBIx::Class::Storage::DBI::Sybase::FreeTDS', @isa); + + bless ($self, $trait_class); + + Class::C3->reinitialize() if DBIx::Class::_ENV_::OLD_MRO; + + $self->_init(@_); + } + + $self->next::method(@_); +} + sub _ping { my $self = shift; @@ -53,17 +78,25 @@ sub _ping { local $dbh->{RaiseError} = 1; local $dbh->{PrintError} = 0; +# FIXME if the main connection goes stale, does opening another for this statement +# really determine anything? + if ($dbh->{syb_no_child_con}) { -# if extra connections are not allowed, then ->ping is reliable - return try { $dbh->ping } catch { 0; }; + return try { + $self->_connect(@{$self->_dbi_connect_info || [] }) + ->do('select 1'); + 1; + } + catch { + 0; + }; } return try { -# XXX if the main connection goes stale, does opening another for this statement -# really determine anything? $dbh->do('select 1'); 1; - } catch { + } + catch { 0; }; } @@ -94,34 +127,7 @@ the Sybase OpenClient libraries were used. sub using_freetds { my $self = shift; - return $self->_get_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 value from your -L if omitted, lastly falls -back to the C<32768> which is the L default. - -=cut - -sub set_textsize { - my $self = shift; - my $text_size = - shift - || - try { $self->_dbi_connect_info->[-1]->{LongReadLen} } - || - 32768; # the DBD::Sybase default - - return unless defined $text_size; - - $self->_dbh->do("SET TEXTSIZE $text_size"); + return ($self->_get_dbh->{syb_oc_version}||'') =~ /freetds/i; } 1; diff --git a/lib/DBIx/Class/Storage/DBI/Sybase/ASE.pm b/lib/DBIx/Class/Storage/DBI/Sybase/ASE.pm index 0e57f02..f70db66 100644 --- a/lib/DBIx/Class/Storage/DBI/Sybase/ASE.pm +++ b/lib/DBIx/Class/Storage/DBI/Sybase/ASE.pm @@ -173,35 +173,30 @@ sub disconnect { $self->next::method; } +# This is only invoked for FreeTDS drivers by ::Storage::DBI::Sybase::FreeTDS +sub _set_autocommit_stmt { + my ($self, $on) = @_; + + return 'SET CHAINED ' . ($on ? 'OFF' : 'ON'); +} + # Set up session settings for Sybase databases for the connection. # # Make sure we have CHAINED mode turned on if AutoCommit is off in non-FreeTDS # DBD::Sybase (since we don't know how DBD::Sybase was compiled.) If however # we're using FreeTDS, CHAINED mode turns on an implicit transaction which we # only want when AutoCommit is off. -# -# Also SET TEXTSIZE for FreeTDS because LongReadLen doesn't work. sub _run_connection_actions { my $self = shift; if ($self->_is_bulk_storage) { -# this should be cleared on every reconnect + # this should be cleared on every reconnect $self->_began_bulk_work(0); return; } - if (not $self->using_freetds) { - $self->_dbh->{syb_chained_txn} = 1; - } else { - # based on LongReadLen in connect_info - $self->set_textsize; - - if ($self->_dbh_autocommit) { - $self->_dbh->do('SET CHAINED OFF'); - } else { - $self->_dbh->do('SET CHAINED ON'); - } - } + $self->_dbh->{syb_chained_txn} = 1 + unless $self->using_freetds; $self->next::method(@_); } @@ -859,7 +854,7 @@ In L to set: On connection for use with L, using L, which you will need to install. -This works for both C and C columns, although +This works for both C and C columns, note that C columns only have minute precision. =cut @@ -883,12 +878,6 @@ sub connect_call_datetime_setup { } -# ->begin_work and such have no effect with FreeTDS but we run them anyway to -# let the DBD keep any state it needs to. -# -# If they ever do start working, the extra statements will do no harm (because -# Sybase supports nested transactions.) - sub _dbh_begin_work { my $self = shift; @@ -898,29 +887,9 @@ sub _dbh_begin_work { $self->next::method(@_); - if ($self->using_freetds) { - $self->_get_dbh->do('BEGIN TRAN'); - } - $self->_began_bulk_work(1) if $self->_is_bulk_storage; } -sub _dbh_commit { - my $self = shift; - if ($self->using_freetds) { - $self->_dbh->do('COMMIT'); - } - return $self->next::method(@_); -} - -sub _dbh_rollback { - my $self = shift; - if ($self->using_freetds) { - $self->_dbh->do('ROLLBACK'); - } - return $self->next::method(@_); -} - # savepoint support using ASE syntax sub _svp_begin { @@ -943,7 +912,7 @@ sub _svp_rollback { =head1 Schema::Loader Support As of version C<0.05000>, L should work well with -most (if not all) versions of Sybase ASE. +most versions of Sybase ASE. =head1 FreeTDS @@ -962,18 +931,22 @@ To see if you're using FreeTDS check C<< $schema->storage->using_freetds >>, or perl -MDBI -le 'my $dbh = DBI->connect($dsn, $user, $pass); print $dbh->{syb_oc_version}' -Some versions of the libraries involved will not support placeholders, in which -case the storage will be reblessed to +It is recommended to set C for your ASE server to C<5.0> in +C. + +Some versions or configurations of the libraries involved will not support +placeholders, in which case the storage will be reblessed to L. In some configurations, placeholders will work but will throw implicit type conversion errors for anything that's not expecting a string. In such a case, the C option from L is automatically set, which you may enable on connection with -L. The type info -for the Cs is taken from the L -definitions in your Result classes, and are mapped to a Sybase type (if it isn't -already) using a mapping based on L. +L. +The type info for the Cs is taken from the +L definitions in your Result classes, and +are mapped to a Sybase type (if it isn't already) using a mapping based on +L. In other configurations, placeholders will work just as they do with the Sybase Open Client libraries. @@ -991,14 +964,14 @@ In addition, they are done on a separate connection so that it's possible to have active cursors when doing an insert. When using C transactions -are disabled, as there are no concurrency issues with C which is a session variable. =head1 TRANSACTIONS -Due to limitations of the TDS protocol, L, or both, you cannot -begin a transaction while there are active cursors, nor can you use multiple -active cursors within a transaction. An active cursor is, for example, a +Due to limitations of the TDS protocol and L, you cannot begin a +transaction while there are active cursors, nor can you use multiple active +cursors within a transaction. An active cursor is, for example, a L that has been executed using C or C but has not been exhausted or L. @@ -1092,7 +1065,7 @@ L call, eg.: B the L calls in your C classes B list columns in database order for this to work. Also, you may have to unset the C environment variable before -loading your app, if it doesn't match the character set of your database. +loading your app, as C is not yet supported in DBD::Sybase . When inserting IMAGE columns using this method, you'll need to use L as well. @@ -1109,6 +1082,7 @@ represent them in your Result classes as: data_type => undef, default_value => \'getdate()', is_nullable => 0, + inflate_datetime => 1, } The C must exist and must be C. Then empty inserts will work @@ -1148,10 +1122,6 @@ Real limits and limited counts using stored procedures deployed on startup. =item * -Adaptive Server Anywhere (ASA) support - -=item * - Blob update with a LIKE query on a blob, without invalidating the WHERE condition. =item * diff --git a/lib/DBIx/Class/Storage/DBI/Sybase/FreeTDS.pm b/lib/DBIx/Class/Storage/DBI/Sybase/FreeTDS.pm new file mode 100644 index 0000000..feb50fe --- /dev/null +++ b/lib/DBIx/Class/Storage/DBI/Sybase/FreeTDS.pm @@ -0,0 +1,116 @@ +package DBIx::Class::Storage::DBI::Sybase::FreeTDS; + +use strict; +use warnings; +use base qw/DBIx::Class::Storage::DBI::Sybase/; +use mro 'c3'; +use Try::Tiny; +use namespace::clean; + +=head1 NAME + +DBIx::Class::Storage::DBI::Sybase - Base class for drivers using L +over FreeTDS. + +=head1 DESCRIPTION + +This is the base class for Storages designed to work with L over +FreeTDS. + +It is a subclass of L. + +=head1 METHODS + +=cut + +# The subclass storage driver defines _set_autocommit_stmt +# for MsSQL it is SET IMPLICIT_TRANSACTIONS ON/OFF +# for proper Sybase it's SET CHAINED ON/OFF +sub _set_autocommit { + my $self = shift; + + if ($self->_dbh_autocommit) { + $self->_dbh->do($self->_set_autocommit_stmt(1)); + } else { + $self->_dbh->do($self->_set_autocommit_stmt(0)); + } +} + +# Handle AutoCommit and SET TEXTSIZE because LongReadLen doesn't work. +# +sub _run_connection_actions { + my $self = shift; + + # based on LongReadLen in connect_info + $self->set_textsize; + + $self->_set_autocommit; + + $self->next::method(@_); +} + +=head2 set_textsize + +When using DBD::Sybase with FreeTDS, 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 value from your +L if omitted, lastly falls +back to the C<32768> which is the L default. + +=cut + +sub set_textsize { + my $self = shift; + my $text_size = + shift + || + try { $self->_dbic_cinnect_attributes->{LongReadLen} } + || + 32768; # the DBD::Sybase default + + $self->_dbh->do("SET TEXTSIZE $text_size"); +} + +sub _dbh_begin_work { + my $self = shift; + + if ($self->{_in_dbh_do}) { + $self->_dbh->do('BEGIN TRAN'); + } + else { + $self->dbh_do(sub { $_[1]->do('BEGIN TRAN') }); + } +} + +sub _dbh_commit { + my $self = shift; + + my $dbh = $self->_dbh + or $self->throw_exception('cannot COMMIT on a disconnected handle'); + + $dbh->do('COMMIT'); +} + +sub _dbh_rollback { + my $self = shift; + + my $dbh = $self->_dbh + or $self->throw_exception('cannot ROLLBACK on a disconnected handle'); + + $dbh->do('ROLLBACK'); +} + +1; + +=head1 AUTHORS + +See L. + +=head1 LICENSE + +You may distribute this code under the same terms as Perl itself. + +=cut diff --git a/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server.pm b/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server.pm index 068a1a2..f1ea17c 100644 --- a/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server.pm +++ b/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server.pm @@ -11,6 +11,29 @@ use mro 'c3'; use DBIx::Class::Carp; +=head1 NAME + +DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server - Support for Microsoft +SQL Server via DBD::Sybase + +=head1 SYNOPSIS + +This subclass supports MSSQL server connections via L. + +=head1 DESCRIPTION + +This driver tries to determine whether your version of L and +supporting libraries (usually FreeTDS) support using placeholders, if not the +storage will be reblessed to +L. + +The MSSQL specific functionality is provided by +L. + +=head1 METHODS + +=cut + __PACKAGE__->datetime_parser_type( 'DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server::DateTime::Format' ); @@ -21,6 +44,19 @@ sub _rebless { return if ref $self ne __PACKAGE__; if (not $self->_use_typeless_placeholders) { + carp <<'EOF' unless $ENV{DBIC_MSSQL_FREETDS_LOWVER_NOWARN}; +Placeholders do not seem to be supported in your configuration of +DBD::Sybase/FreeTDS. + +This means you are taking a large performance hit, as caching of prepared +statements is disabled. + +Make sure to configure your server with "tds version" of 8.0 or 7.0 in +/etc/freetds/freetds.conf . + +To turn off this warning, set the DBIC_MSSQL_FREETDS_LOWVER_NOWARN environment +variable. +EOF require DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server::NoBindVars; bless $self, @@ -29,35 +65,11 @@ sub _rebless { } } -sub _run_connection_actions { - my $self = shift; - - # LongReadLen doesn't work with MSSQL through DBD::Sybase, and the default is - # huge on some versions of SQL server and can cause memory problems, so we - # fix it up here (see ::DBI::Sybase.pm) - $self->set_textsize; - - $self->next::method(@_); -} - -sub _dbh_begin_work { - my $self = shift; - - $self->_get_dbh->do('BEGIN TRAN'); -} - -sub _dbh_commit { - my $self = shift; - my $dbh = $self->_dbh - or $self->throw_exception('cannot COMMIT on a disconnected handle'); - $dbh->do('COMMIT'); -} +# invoked only if DBD::Sybase is compiled against FreeTDS +sub _set_autocommit_stmt { + my ($self, $on) = @_; -sub _dbh_rollback { - my $self = shift; - my $dbh = $self->_dbh - or $self->throw_exception('cannot ROLLBACK on a disconnected handle'); - $dbh->do('ROLLBACK'); + return 'SET IMPLICIT_TRANSACTIONS ' . ($on ? 'OFF' : 'ON'); } sub _get_server_version { @@ -138,25 +150,6 @@ sub format_datetime { 1; -=head1 NAME - -DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server - Support for Microsoft -SQL Server via DBD::Sybase - -=head1 SYNOPSIS - -This subclass supports MSSQL server connections via L. - -=head1 DESCRIPTION - -This driver tries to determine whether your version of L and -supporting libraries (usually FreeTDS) support using placeholders, if not the -storage will be reblessed to -L. - -The MSSQL specific functionality is provided by -L. - =head1 AUTHOR See L. diff --git a/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server/NoBindVars.pm b/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server/NoBindVars.pm index 622cf1e..5d266bc 100644 --- a/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server/NoBindVars.pm +++ b/lib/DBIx/Class/Storage/DBI/Sybase/Microsoft_SQL_Server/NoBindVars.pm @@ -12,6 +12,8 @@ use mro 'c3'; sub _init { my $self = shift; $self->disable_sth_caching(1); + + $self->next::method(@_); } 1; diff --git a/t/04_c3_mro.t b/t/04_c3_mro.t index 0c22bab..2230d56 100644 --- a/t/04_c3_mro.t +++ b/t/04_c3_mro.t @@ -58,6 +58,7 @@ is_deeply ( ); my $storage = DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server->new; +$storage->connect_info(['dbi:SQLite::memory:']); # determine_driver's init() connects for this subclass $storage->_determine_driver; is ( $storage->can('sql_limit_dialect'), diff --git a/t/74mssql.t b/t/74mssql.t index 223709d..57d7c69 100644 --- a/t/74mssql.t +++ b/t/74mssql.t @@ -42,6 +42,8 @@ for my $storage_type (@test_storages) { $schema->storage->_use_typeless_placeholders (0); } + local $ENV{DBIC_MSSQL_FREETDS_LOWVER_NOWARN} = 1; # disable nobindvars warning + $schema->storage->ensure_connected; if ($storage_type =~ /NoBindVars\z/) { @@ -192,6 +194,66 @@ SQL $rs->delete; } + # test transaction handling on a disconnected handle + my $wrappers = { + no_transaction => sub { shift->() }, + txn_do => sub { my $code = shift; $schema->txn_do(sub { $code->() } ) }, + txn_begin => sub { $schema->txn_begin; shift->(); $schema->txn_commit }, + txn_guard => sub { my $g = $schema->txn_scope_guard; shift->(); $g->commit }, + }; + for my $wrapper (keys %$wrappers) { + $rs->delete; + + # a reconnect should trigger on next action + $schema->storage->_get_dbh->disconnect; + + lives_and { + $wrappers->{$wrapper}->( sub { + $rs->create({ amount => 900 + $_ }) for 1..3; + }); + is $rs->count, 3; + } "transaction on disconnected handle with $wrapper wrapper"; + } + + TODO: { + local $TODO = 'Transaction handling with multiple active statements will ' + .'need eager cursor support.'; + + # test transaction handling on a disconnected handle with multiple active + # statements + my $wrappers = { + no_transaction => sub { shift->() }, + txn_do => sub { my $code = shift; $schema->txn_do(sub { $code->() } ) }, + txn_begin => sub { $schema->txn_begin; shift->(); $schema->txn_commit }, + txn_guard => sub { my $g = $schema->txn_scope_guard; shift->(); $g->commit }, + }; + for my $wrapper (keys %$wrappers) { + $rs->reset; + $rs->delete; + $rs->create({ amount => 1000 + $_ }) for (1..3); + + my $artist_rs = $schema->resultset('Artist')->search({ + name => { -like => 'Artist %' } + });; + + $rs->next; + + my $map = [ ['Artist 1', '1002.00'], ['Artist 2', '1003.00'] ]; + + lives_and { + my @results; + + $wrappers->{$wrapper}->( sub { + while (my $money = $rs->next) { + my $artist = $artist_rs->next; + push @results, [ $artist->name, $money->amount ]; + }; + }); + + is_deeply \@results, $map; + } "transactions with multiple active statement with $wrapper wrapper"; + } + } # test RNO detection when version detection fails SKIP: { @@ -231,6 +293,31 @@ lives_ok (sub { is ($artist->id, 1, 'Artist retrieved successfully'); }, 'Query-induced autoconnect works'); +# test AutoCommit=0 +{ + local $ENV{DBIC_UNSAFE_AUTOCOMMIT_OK} = 1; + my $schema2 = DBICTest::Schema->connect($dsn, $user, $pass, { AutoCommit => 0 }); + + my $rs = $schema2->resultset('Money'); + + $rs->delete; + $schema2->txn_commit; + + is $rs->count, 0, 'initially empty' + || diag ('Found row with amount ' . $_->amount) for $rs->all; + + $rs->create({ amount => 3000 }); + $schema2->txn_rollback; + + is $rs->count, 0, 'rolled back in AutoCommit=0' + || diag ('Found row with amount ' . $_->amount) for $rs->all; + + $rs->create({ amount => 4000 }); + $schema2->txn_commit; + + cmp_ok $rs->first->amount, '==', 4000, 'committed in AutoCommit=0'; +} + done_testing; # clean up our mess