From: Peter Rabbitson Date: Mon, 23 Nov 2009 00:06:48 +0000 (+0000) Subject: refactor part1 X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=057db5cedeec00f32bebb710756587ba4d0428ae;p=dbsrgits%2FDBIx-Class-Historic.git refactor part1 --- diff --git a/lib/DBIx/Class/Storage/DBI/Sybase.pm b/lib/DBIx/Class/Storage/DBI/Sybase.pm index 4b1c8d6..ac3adf9 100644 --- a/lib/DBIx/Class/Storage/DBI/Sybase.pm +++ b/lib/DBIx/Class/Storage/DBI/Sybase.pm @@ -3,54 +3,17 @@ package DBIx::Class::Storage::DBI::Sybase; use strict; use warnings; -use base qw/ - DBIx::Class::Storage::DBI::Sybase::Common - DBIx::Class::Storage::DBI::AutoCast -/; -use mro 'c3'; -use Carp::Clan qw/^DBIx::Class/; -use List::Util(); -use Sub::Name(); -use Data::Dumper::Concise(); - -__PACKAGE__->mk_group_accessors('simple' => - qw/_identity _blob_log_on_update _writer_storage _is_extra_storage - _bulk_storage _is_bulk_storage _began_bulk_work - _bulk_disabled_due_to_coderef_connect_info_warned - _identity_method/ -); - -my @also_proxy_to_extra_storages = qw/ - connect_call_set_auto_cast auto_cast connect_call_blob_setup - connect_call_datetime_setup - - disconnect _connect_info _sql_maker _sql_maker_opts disable_sth_caching - auto_savepoint unsafe cursor_class debug debugobj schema -/; +use base qw/DBIx::Class::Storage::DBI/; =head1 NAME -DBIx::Class::Storage::DBI::Sybase - Sybase support for DBIx::Class - -=head1 SYNOPSIS - -This subclass supports L for real Sybase databases. If you are -using an MSSQL database via L, your storage will be reblessed to -L. +DBIx::Class::Storage::DBI::Sybase::Common - Base class for drivers using +DBD::Sybase =head1 DESCRIPTION -If your version of Sybase does not support placeholders, then your storage -will be reblessed to L. You can -also enable that driver explicitly, see the documentation for more details. - -With this driver there is unfortunately no way to get the C -without doing a C, which is the only way to get the C value in this -mode. - -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. This is done safely in a transaction +(locking the table.) See L. + +A recommended L setting: + + on_connect_call => [['datetime_setup'], ['blob_setup', log_on_update => 0]] + +=head1 METHODS + +=cut + +sub _rebless { + my $self = shift; + + my $no_bind_vars = __PACKAGE__ . '::NoBindVars'; + + if ($self->using_freetds) { + carp <<'EOF' unless $ENV{DBIC_SYBASE_FREETDS_NOWARN}; + +You are using FreeTDS with Sybase. + +We will do our best to support this configuration, but please consider this +support experimental. + +TEXT/IMAGE columns will definitely not work. + +You are encouraged to recompile DBD::Sybase with the Sybase Open Client libraries +instead. + +See perldoc DBIx::Class::Storage::DBI::Sybase::ASE for more details. + +To turn off this warning set the DBIC_SYBASE_FREETDS_NOWARN environment +variable. +EOF + + if (not $self->_typeless_placeholders_supported) { + if ($self->_placeholders_supported) { + $self->auto_cast(1); + } + else { + $self->ensure_class_loaded($no_bind_vars); + bless $self, $no_bind_vars; + $self->_rebless; + } + } + } + + elsif (not $self->_get_dbh->{syb_dynamic_supported}) { + # not necessarily FreeTDS, but no placeholders nevertheless + $self->ensure_class_loaded($no_bind_vars); + bless $self, $no_bind_vars; + $self->_rebless; + } + # this is highly unlikely, but we check just in case + elsif (not $self->_typeless_placeholders_supported) { + $self->auto_cast(1); + } +} + +sub _init { + my $self = shift; + $self->_set_max_connect(256); + +# create storage for insert/(update blob) transactions, +# unless this is that storage + return if $self->_is_extra_storage; + + my $writer_storage = (ref $self)->new; + + $writer_storage->_is_extra_storage(1); + $writer_storage->connect_info($self->connect_info); + $writer_storage->auto_cast($self->auto_cast); + + $self->_writer_storage($writer_storage); + +# create a bulk storage unless connect_info is a coderef + return if ref($self->_dbi_connect_info->[0]) eq 'CODE'; + + my $bulk_storage = (ref $self)->new; + + $bulk_storage->_is_extra_storage(1); + $bulk_storage->_is_bulk_storage(1); # for special ->disconnect acrobatics + $bulk_storage->connect_info($self->connect_info); + +# this is why + $bulk_storage->_dbi_connect_info->[0] .= ';bulkLogin=1'; + + $self->_bulk_storage($bulk_storage); +} + +for my $method (@also_proxy_to_extra_storages) { + no strict 'refs'; + no warnings 'redefine'; + + my $replaced = __PACKAGE__->can($method); + + *{$method} = Sub::Name::subname $method => sub { + my $self = shift; + $self->_writer_storage->$replaced(@_) if $self->_writer_storage; + $self->_bulk_storage->$replaced(@_) if $self->_bulk_storage; + return $self->$replaced(@_); + }; +} + +sub disconnect { + my $self = shift; + +# Even though we call $sth->finish for uses off the bulk API, there's still an +# "active statement" warning on disconnect, which we throw away here. +# This is due to the bug described in insert_bulk. +# Currently a noop because 'prepare' is used instead of 'prepare_cached'. + local $SIG{__WARN__} = sub { + warn $_[0] unless $_[0] =~ /active statement/i; + } if $self->_is_bulk_storage; + +# so that next transaction gets a dbh + $self->_began_bulk_work(0) if $self->_is_bulk_storage; + + $self->next::method; +} + +# 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 + $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->next::method(@_); +} + +=head2 connect_call_blob_setup + +Used as: + + on_connect_call => [ [ 'blob_setup', log_on_update => 0 ] ] + +Does C<< $dbh->{syb_binary_images} = 1; >> to return C data as raw binary +instead of as a hex string. + +Recommended. + +Also sets the C value for blob write operations. The default is +C<1>, but C<0> is better if your database is configured for it. + +See +L. + +=cut + +sub connect_call_blob_setup { + my $self = shift; + my %args = @_; + my $dbh = $self->_dbh; + $dbh->{syb_binary_images} = 1; + + $self->_blob_log_on_update($args{log_on_update}) + if exists $args{log_on_update}; +} + +sub _is_lob_type { + my $self = shift; + my $type = shift; + $type && $type =~ /(?:text|image|lob|bytea|binary|memo)/i; +} + +sub _is_lob_column { + my ($self, $source, $column) = @_; + + return $self->_is_lob_type($source->column_info($column)->{data_type}); +} + +sub _prep_for_execute { + my $self = shift; + my ($op, $extra_bind, $ident, $args) = @_; + + my ($sql, $bind) = $self->next::method (@_); + + my $table = Scalar::Util::blessed($ident) ? $ident->from : $ident; + + my $bind_info = $self->_resolve_column_info( + $ident, [map $_->[0], @{$bind}] + ); + my $bound_identity_col = List::Util::first + { $bind_info->{$_}{is_auto_increment} } + (keys %$bind_info) + ; + my $identity_col = Scalar::Util::blessed($ident) && + List::Util::first + { $ident->column_info($_)->{is_auto_increment} } + $ident->columns + ; + + if (($op eq 'insert' && $bound_identity_col) || + ($op eq 'update' && exists $args->[0]{$identity_col})) { + $sql = join ("\n", + $self->_set_table_identity_sql($op => $table, 'on'), + $sql, + $self->_set_table_identity_sql($op => $table, 'off'), + ); + } + + if ($op eq 'insert' && (not $bound_identity_col) && $identity_col && + (not $self->{insert_bulk})) { + $sql = + "$sql\n" . + $self->_fetch_identity_sql($ident, $identity_col); + } + + return ($sql, $bind); +} + +sub _set_table_identity_sql { + my ($self, $op, $table, $on_off) = @_; + + return sprintf 'SET IDENTITY_%s %s %s', + uc($op), $self->sql_maker->_quote($table), uc($on_off); +} + +# Stolen from SQLT, with some modifications. This is a makeshift +# solution before a sane type-mapping library is available, thus +# the 'our' for easy overrides. +our %TYPE_MAPPING = ( + number => 'numeric', + money => 'money', + varchar => 'varchar', + varchar2 => 'varchar', + timestamp => 'datetime', + text => 'varchar', + real => 'double precision', + comment => 'text', + bit => 'bit', + tinyint => 'smallint', + float => 'double precision', + serial => 'numeric', + bigserial => 'numeric', + boolean => 'varchar', + long => 'varchar', +); + +sub _native_data_type { + my ($self, $type) = @_; + + $type = lc $type; + $type =~ s/\s* identity//x; + + return uc($TYPE_MAPPING{$type} || $type); +} + +sub _fetch_identity_sql { + my ($self, $source, $col) = @_; + + return sprintf ("SELECT MAX(%s) FROM %s", + map { $self->sql_maker->_quote ($_) } ($col, $source->from) + ); +} + +sub _execute { + my $self = shift; + my ($op) = @_; + + my ($rv, $sth, @bind) = $self->dbh_do($self->can('_dbh_execute'), @_); + + if ($op eq 'insert') { + $self->_identity($sth->fetchrow_array); + $sth->finish; + } + + return wantarray ? ($rv, $sth, @bind) : $rv; +} + +sub last_insert_id { shift->_identity } + +# handles TEXT/IMAGE and transaction for last_insert_id +sub insert { + my $self = shift; + my ($source, $to_insert) = @_; + + my $identity_col = (List::Util::first + { $source->column_info($_)->{is_auto_increment} } + $source->columns) || ''; + + # check for empty insert + # INSERT INTO foo DEFAULT VALUES -- does not work with Sybase + # try to insert explicit 'DEFAULT's instead (except for identity) + if (not %$to_insert) { + for my $col ($source->columns) { + next if $col eq $identity_col; + $to_insert->{$col} = \'DEFAULT'; + } + } + + my $blob_cols = $self->_remove_blob_cols($source, $to_insert); + + # do we need the horrific SELECT MAX(COL) hack? + my $dumb_last_insert_id = + $identity_col + && (not exists $to_insert->{$identity_col}) + && ($self->_identity_method||'') ne '@@IDENTITY'; + + my $next = $self->next::can; + + # we are already in a transaction, or there are no blobs + # and we don't need the PK - just (try to) do it + if ($self->{transaction_depth} + || (!$blob_cols && !$dumb_last_insert_id) + ) { + return $self->_insert ( + $next, $source, $to_insert, $blob_cols, $identity_col + ); + } + + # otherwise use the _writer_storage to do the insert+transaction on another + # connection + my $guard = $self->_writer_storage->txn_scope_guard; + + my $updated_cols = $self->_writer_storage->_insert ( + $next, $source, $to_insert, $blob_cols, $identity_col + ); + + $self->_identity($self->_writer_storage->_identity); + + $guard->commit; + + return $updated_cols; +} + +sub _insert { + my ($self, $next, $source, $to_insert, $blob_cols, $identity_col) = @_; + + my $updated_cols = $self->$next ($source, $to_insert); + + my $final_row = { + ($identity_col ? + ($identity_col => $self->last_insert_id($source, $identity_col)) : ()), + %$to_insert, + %$updated_cols, + }; + + $self->_insert_blobs ($source, $blob_cols, $final_row) if $blob_cols; + + return $updated_cols; +} + +sub update { + my $self = shift; + my ($source, $fields, $where, @rest) = @_; + + my $wantarray = wantarray; + + my $blob_cols = $self->_remove_blob_cols($source, $fields); + + my $table = $source->name; + + my $identity_col = List::Util::first + { $source->column_info($_)->{is_auto_increment} } + $source->columns; + + my $is_identity_update = $identity_col && defined $fields->{$identity_col}; + + return $self->next::method(@_) unless $blob_cols; + +# If there are any blobs in $where, Sybase will return a descriptive error +# message. +# XXX blobs can still be used with a LIKE query, and this should be handled. + +# update+blob update(s) done atomically on separate connection + $self = $self->_writer_storage; + + my $guard = $self->txn_scope_guard; + +# First update the blob columns to be updated to '' (taken from $fields, where +# it is originally put by _remove_blob_cols .) + my %blobs_to_empty = map { ($_ => delete $fields->{$_}) } keys %$blob_cols; + +# We can't only update NULL blobs, because blobs cannot be in the WHERE clause. + + $self->next::method($source, \%blobs_to_empty, $where, @rest); + +# Now update the blobs before the other columns in case the update of other +# columns makes the search condition invalid. + $self->_update_blobs($source, $blob_cols, $where); + + my @res; + if (%$fields) { + if ($wantarray) { + @res = $self->next::method(@_); + } + elsif (defined $wantarray) { + $res[0] = $self->next::method(@_); + } + else { + $self->next::method(@_); + } + } + + $guard->commit; + + return $wantarray ? @res : $res[0]; +} + +sub insert_bulk { + my $self = shift; + my ($source, $cols, $data) = @_; + + my $identity_col = List::Util::first + { $source->column_info($_)->{is_auto_increment} } + $source->columns; + + my $is_identity_insert = (List::Util::first + { $_ eq $identity_col } + @{$cols} + ) ? 1 : 0; + + my @source_columns = $source->columns; + + my $use_bulk_api = + $self->_bulk_storage && + $self->_get_dbh->{syb_has_blk}; + + if ((not $use_bulk_api) + && + (ref($self->_dbi_connect_info->[0]) eq 'CODE') + && + (not $self->_bulk_disabled_due_to_coderef_connect_info_warned)) { + carp <<'EOF'; +Bulk API support disabled due to use of a CODEREF connect_info. Reverting to +regular array inserts. +EOF + $self->_bulk_disabled_due_to_coderef_connect_info_warned(1); + } + + if (not $use_bulk_api) { + my $blob_cols = $self->_remove_blob_cols_array($source, $cols, $data); + +# _execute_array uses a txn anyway, but it ends too early in case we need to +# select max(col) to get the identity for inserting blobs. + ($self, my $guard) = $self->{transaction_depth} == 0 ? + ($self->_writer_storage, $self->_writer_storage->txn_scope_guard) + : + ($self, undef); + + local $self->{insert_bulk} = 1; + + $self->next::method(@_); + + if ($blob_cols) { + if ($is_identity_insert) { + $self->_insert_blobs_array ($source, $blob_cols, $cols, $data); + } + else { + my @cols_with_identities = (@$cols, $identity_col); + + ## calculate identities + # XXX This assumes identities always increase by 1, which may or may not + # be true. + my ($last_identity) = + $self->_dbh->selectrow_array ( + $self->_fetch_identity_sql($source, $identity_col) + ); + my @identities = (($last_identity - @$data + 1) .. $last_identity); + + my @data_with_identities = map [@$_, shift @identities], @$data; + + $self->_insert_blobs_array ( + $source, $blob_cols, \@cols_with_identities, \@data_with_identities + ); + } + } + + $guard->commit if $guard; + + return; + } + +# otherwise, use the bulk API + +# rearrange @$data so that columns are in database order + my %orig_idx; + @orig_idx{@$cols} = 0..$#$cols; + + my %new_idx; + @new_idx{@source_columns} = 0..$#source_columns; + + my @new_data; + for my $datum (@$data) { + my $new_datum = []; + for my $col (@source_columns) { +# identity data will be 'undef' if not $is_identity_insert +# columns with defaults will also be 'undef' + $new_datum->[ $new_idx{$col} ] = + exists $orig_idx{$col} ? $datum->[ $orig_idx{$col} ] : undef; + } + push @new_data, $new_datum; + } + +# bcp identity index is 1-based + my $identity_idx = exists $new_idx{$identity_col} ? + $new_idx{$identity_col} + 1 : 0; + +## Set a client-side conversion error handler, straight from DBD::Sybase docs. +# This ignores any data conversion errors detected by the client side libs, as +# they are usually harmless. + my $orig_cslib_cb = DBD::Sybase::set_cslib_cb( + Sub::Name::subname insert_bulk => sub { + my ($layer, $origin, $severity, $errno, $errmsg, $osmsg, $blkmsg) = @_; + + return 1 if $errno == 36; + + carp + "Layer: $layer, Origin: $origin, Severity: $severity, Error: $errno" . + ($errmsg ? "\n$errmsg" : '') . + ($osmsg ? "\n$osmsg" : '') . + ($blkmsg ? "\n$blkmsg" : ''); + + return 0; + }); + + eval { + my $bulk = $self->_bulk_storage; + + my $guard = $bulk->txn_scope_guard; + +## XXX get this to work instead of our own $sth +## will require SQLA or *Hacks changes for ordered columns +# $bulk->next::method($source, \@source_columns, \@new_data, { +# syb_bcp_attribs => { +# identity_flag => $is_identity_insert, +# identity_column => $identity_idx, +# } +# }); + my $sql = 'INSERT INTO ' . + $bulk->sql_maker->_quote($source->name) . ' (' . +# colname list is ignored for BCP, but does no harm + (join ', ', map $bulk->sql_maker->_quote($_), @source_columns) . ') '. + ' VALUES ('. (join ', ', ('?') x @source_columns) . ')'; + +## XXX there's a bug in the DBD::Sybase bulk support that makes $sth->finish for +## a prepare_cached statement ineffective. Replace with ->sth when fixed, or +## better yet the version above. Should be fixed in DBD::Sybase . + my $sth = $bulk->_get_dbh->prepare($sql, +# 'insert', # op + { + syb_bcp_attribs => { + identity_flag => $is_identity_insert, + identity_column => $identity_idx, + } + } + ); + + my @bind = do { + my $idx = 0; + map [ $_, $idx++ ], @source_columns; + }; + + $self->_execute_array( + $source, $sth, \@bind, \@source_columns, \@new_data, sub { + $guard->commit + } + ); + + $bulk->_query_end($sql); + }; + + my $exception = $@; + DBD::Sybase::set_cslib_cb($orig_cslib_cb); + + if ($exception =~ /-Y option/) { + carp <<"EOF"; + +Sybase bulk API operation failed due to character set incompatibility, reverting +to regular array inserts: + +*** Try unsetting the LANG environment variable. + +$exception +EOF + $self->_bulk_storage(undef); + unshift @_, $self; + goto \&insert_bulk; + } + elsif ($exception) { +# rollback makes the bulkLogin connection unusable + $self->_bulk_storage->disconnect; + $self->throw_exception($exception); + } +} + +sub _dbh_execute_array { + my ($self, $sth, $tuple_status, $cb) = @_; + + my $rv = $self->next::method($sth, $tuple_status); + $cb->() if $cb; + + return $rv; +} + +# Make sure blobs are not bound as placeholders, and return any non-empty ones +# as a hash. +sub _remove_blob_cols { + my ($self, $source, $fields) = @_; + + my %blob_cols; + + for my $col (keys %$fields) { + if ($self->_is_lob_column($source, $col)) { + my $blob_val = delete $fields->{$col}; + if (not defined $blob_val) { + $fields->{$col} = \'NULL'; + } + else { + $fields->{$col} = \"''"; + $blob_cols{$col} = $blob_val unless $blob_val eq ''; + } + } + } + + return %blob_cols ? \%blob_cols : undef; +} + +# same for insert_bulk +sub _remove_blob_cols_array { + my ($self, $source, $cols, $data) = @_; + + my @blob_cols; + + for my $i (0..$#$cols) { + my $col = $cols->[$i]; + + if ($self->_is_lob_column($source, $col)) { + for my $j (0..$#$data) { + my $blob_val = delete $data->[$j][$i]; + if (not defined $blob_val) { + $data->[$j][$i] = \'NULL'; + } + else { + $data->[$j][$i] = \"''"; + $blob_cols[$j][$i] = $blob_val + unless $blob_val eq ''; + } + } + } + } + + return @blob_cols ? \@blob_cols : undef; +} + +sub _update_blobs { + my ($self, $source, $blob_cols, $where) = @_; + + my (@primary_cols) = $source->primary_columns; + + $self->throw_exception('Cannot update TEXT/IMAGE column(s) without a primary key') + unless @primary_cols; + +# check if we're updating a single row by PK + my $pk_cols_in_where = 0; + for my $col (@primary_cols) { + $pk_cols_in_where++ if defined $where->{$col}; + } + my @rows; + + if ($pk_cols_in_where == @primary_cols) { + my %row_to_update; + @row_to_update{@primary_cols} = @{$where}{@primary_cols}; + @rows = \%row_to_update; + } else { + my $cursor = $self->select ($source, \@primary_cols, $where, {}); + @rows = map { + my %row; @row{@primary_cols} = @$_; \%row + } $cursor->all; + } + + for my $row (@rows) { + $self->_insert_blobs($source, $blob_cols, $row); + } +} + +sub _insert_blobs { + my ($self, $source, $blob_cols, $row) = @_; + my $dbh = $self->_get_dbh; + + my $table = $source->name; + + my %row = %$row; + my (@primary_cols) = $source->primary_columns; + + $self->throw_exception('Cannot update TEXT/IMAGE column(s) without a primary key') + unless @primary_cols; + + $self->throw_exception('Cannot update TEXT/IMAGE column(s) without primary key values') + if ((grep { defined $row{$_} } @primary_cols) != @primary_cols); + + for my $col (keys %$blob_cols) { + my $blob = $blob_cols->{$col}; + + my %where = map { ($_, $row{$_}) } @primary_cols; + + my $cursor = $self->select ($source, [$col], \%where, {}); + $cursor->next; + my $sth = $cursor->sth; + + if (not $sth) { + + $self->throw_exception( + "Could not find row in table '$table' for blob update:\n" + . Data::Dumper::Concise::Dumper (\%where) + ); + } + + eval { + do { + $sth->func('CS_GET', 1, 'ct_data_info') or die $sth->errstr; + } while $sth->fetch; + + $sth->func('ct_prepare_send') or die $sth->errstr; + + my $log_on_update = $self->_blob_log_on_update; + $log_on_update = 1 if not defined $log_on_update; + + $sth->func('CS_SET', 1, { + total_txtlen => length($blob), + log_on_update => $log_on_update + }, 'ct_data_info') or die $sth->errstr; + + $sth->func($blob, length($blob), 'ct_send_data') or die $sth->errstr; + + $sth->func('ct_finish_send') or die $sth->errstr; + }; + my $exception = $@; + $sth->finish if $sth; + if ($exception) { + if ($self->using_freetds) { + $self->throw_exception ( + 'TEXT/IMAGE operation failed, probably because you are using FreeTDS: ' + . $exception + ); + } else { + $self->throw_exception($exception); + } + } + } +} + +sub _insert_blobs_array { + my ($self, $source, $blob_cols, $cols, $data) = @_; + + for my $i (0..$#$data) { + my $datum = $data->[$i]; + + my %row; + @row{ @$cols } = @$datum; + + my %blob_vals; + for my $j (0..$#$cols) { + if (exists $blob_cols->[$i][$j]) { + $blob_vals{ $cols->[$j] } = $blob_cols->[$i][$j]; + } + } + + $self->_insert_blobs ($source, \%blob_vals, \%row); + } +} + +=head2 connect_call_datetime_setup + +Used as: + + on_connect_call => 'datetime_setup' + +In L to set: + + $dbh->syb_date_fmt('ISO_strict'); # output fmt: 2004-08-21T14:36:48.080Z + $dbh->do('set dateformat mdy'); # input fmt: 08/13/1979 18:08:55.080 + +On connection for use with L, using +L, which you will need to install. + +This works for both C and C columns, although +C columns only have minute precision. + +=cut + +{ + my $old_dbd_warned = 0; + + sub connect_call_datetime_setup { + my $self = shift; + my $dbh = $self->_get_dbh; + + if ($dbh->can('syb_date_fmt')) { + # amazingly, this works with FreeTDS + $dbh->syb_date_fmt('ISO_strict'); + } elsif (not $old_dbd_warned) { + carp "Your DBD::Sybase is too old to support ". + "DBIx::Class::InflateColumn::DateTime, please upgrade!"; + $old_dbd_warned = 1; + } + + $dbh->do('SET DATEFORMAT mdy'); + + 1; + } +} + +sub datetime_parser_type { "DateTime::Format::Sybase" } + +# ->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; + +# bulkLogin=1 connections are always in a transaction, and can only call BEGIN +# TRAN once. However, we need to make sure there's a $dbh. + return if $self->_is_bulk_storage && $self->_dbh && $self->_began_bulk_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 $self->next::method(@_); +} + +# savepoint support using ASE syntax + +sub _svp_begin { + my ($self, $name) = @_; + + $self->_get_dbh->do("SAVE TRANSACTION $name"); +} + +# A new SAVE TRANSACTION with the same name releases the previous one. +sub _svp_release { 1 } + +sub _svp_rollback { + my ($self, $name) = @_; + + $self->_get_dbh->do("ROLLBACK TRANSACTION $name"); +} + +1; + +=head1 Schema::Loader Support + +There is an experimental branch of L that will +allow you to dump a schema from most (if not all) versions of Sybase. + +It is available via subversion from: + + http://dev.catalyst.perl.org/repos/bast/branches/DBIx-Class-Schema-Loader/current/ + +=head1 FreeTDS + +This driver supports L compiled against FreeTDS +(L) to the best of our ability, however it is +recommended that you recompile L against the Sybase Open Client +libraries. They are a part of the Sybase ASE distribution: + +The Open Client FAQ is here: +L. + +Sybase ASE for Linux (which comes with the Open Client libraries) may be +downloaded here: L. + +To see if you're using FreeTDS check C<< $schema->storage->using_freetds >>, or run: + + 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 +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. + +In other configurations, placeholers will work just as they do with the Sybase +Open Client libraries. + +Inserts or updates of TEXT/IMAGE columns will B work with FreeTDS. + +=head1 INSERTS WITH PLACEHOLDERS + +With placeholders enabled, inserts are done in a transaction so that there are +no concurrency issues with getting the inserted identity value using +C as +it's 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 +L that has been executed using C or +C but has not been exhausted or L. + +For example, this will not work: + + $schema->txn_do(sub { + my $rs = $schema->resultset('Book'); + while (my $row = $rs->next) { + $schema->resultset('MetaData')->create({ + book_id => $row->id, + ... + }); + } + }); + +This won't either: + + my $first_row = $large_rs->first; + $schema->txn_do(sub { ... }); + +Transactions done for inserts in C mode when placeholders are in use +are not affected, as they are done on an extra database handle. + +Some workarounds: + +=over 4 + +=item * use L + +=item * L another L + +=item * load the data from your cursor with L + +=back + +=head1 MAXIMUM CONNECTIONS + +The TDS protocol makes separate connections to the server for active statements +in the background. By default the number of such connections is limited to 25, +on both the client side and the server side. + +This is a bit too low for a complex L application, so on connection +the client side setting is set to C<256> (see L.) You +can override it to whatever setting you like in the DSN. + +See +L +for information on changing the setting on the server side. + +=head1 DATES + +See L to setup date formats +for L. + +=head1 TEXT/IMAGE COLUMNS + +L compiled with FreeTDS will B allow you to insert or update +C columns. + +Setting C<< $dbh->{LongReadLen} >> will also not work with FreeTDS use either: + + $schema->storage->dbh->do("SET TEXTSIZE $bytes"); + +or + + $schema->storage->set_textsize($bytes); + +instead. + +However, the C you pass in +L is used to execute the equivalent +C command on connection. + +See L for a L +setting you need to work with C columns. + +=head1 BULK API + +The experimental L Bulk API support is used for +L in B context, in a transaction +on a separate connection. + +To use this feature effectively, use a large number of rows for each +L call, eg.: + + while (my $rows = $data_source->get_100_rows()) { + $rs->populate($rows); + } + +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. + +When inserting IMAGE columns using this method, you'll need to use +L as well. + +=head1 TODO + +=over + +=item * + +Transitions to AutoCommit=0 (starting a transaction) mode by exhausting +any active cursors, using eager cursors. + +=item * + +Real limits and limited counts using stored procedures deployed on startup. + +=item * + +Adaptive Server Anywhere (ASA) support, with possible SQLA::Limit support. + +=item * + +Blob update with a LIKE query on a blob, without invalidating the WHERE condition. + +=item * + +bulk_insert using prepare_cached (see comments.) + +=back + +=head1 AUTHOR + +See L. + +=head1 LICENSE + +You may distribute this code under the same terms as Perl itself. + +=cut +# vim:sts=2 sw=2: diff --git a/lib/DBIx/Class/Storage/DBI/Sybase/NoBindVars.pm b/lib/DBIx/Class/Storage/DBI/Sybase/SQL_Server/NoBindVars.pm similarity index 89% rename from lib/DBIx/Class/Storage/DBI/Sybase/NoBindVars.pm rename to lib/DBIx/Class/Storage/DBI/Sybase/SQL_Server/NoBindVars.pm index 32908ee..dc8bf34 100644 --- a/lib/DBIx/Class/Storage/DBI/Sybase/NoBindVars.pm +++ b/lib/DBIx/Class/Storage/DBI/Sybase/SQL_Server/NoBindVars.pm @@ -1,8 +1,8 @@ -package DBIx::Class::Storage::DBI::Sybase::NoBindVars; +package DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars; use base qw/ DBIx::Class::Storage::DBI::NoBindVars - DBIx::Class::Storage::DBI::Sybase + DBIx::Class::Storage::DBI::Sybase::ASE /; use mro 'c3'; use List::Util (); @@ -63,8 +63,8 @@ sub _prep_interpolated_value { =head1 NAME -DBIx::Class::Storage::DBI::Sybase::NoBindVars - Storage::DBI subclass for Sybase -without placeholder support +DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars - Storage::DBI subclass for +Sybase ASE without placeholder support =head1 DESCRIPTION @@ -74,7 +74,7 @@ use to connect to it, do not support placeholders. You can also enable this driver explicitly using: my $schema = SchemaClass->clone; - $schema->storage_type('::DBI::Sybase::NoBindVars'); + $schema->storage_type('::DBI::Sybase::ASE::NoBindVars'); $schema->connect($dsn, $user, $pass, \%opts); See the discussion in L<< DBD::Sybase/Using ? Placeholders & bind parameters to