1 package DBIx::Class::Storage::DBI::Sybase::ASE;
7 DBIx::Class::Storage::DBI::Sybase
8 DBIx::Class::Storage::DBI::AutoCast
11 use Carp::Clan qw/^DBIx::Class/;
15 use Data::Dumper::Concise();
18 __PACKAGE__->mk_group_accessors('simple' =>
19 qw/_identity _blob_log_on_update _writer_storage _is_extra_storage
20 _bulk_storage _is_bulk_storage _began_bulk_work
21 _bulk_disabled_due_to_coderef_connect_info_warned
25 my @also_proxy_to_extra_storages = qw/
26 connect_call_set_auto_cast auto_cast connect_call_blob_setup
27 connect_call_datetime_setup
29 disconnect _connect_info _sql_maker _sql_maker_opts disable_sth_caching
30 auto_savepoint unsafe cursor_class debug debugobj schema
35 DBIx::Class::Storage::DBI::Sybase::ASE - Sybase ASE SQL Server support for
40 This subclass supports L<DBD::Sybase> for real (non-Microsoft) Sybase databases.
44 If your version of Sybase does not support placeholders, then your storage will
45 be reblessed to L<DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars>.
46 You can also enable that driver explicitly, see the documentation for more
49 With this driver there is unfortunately no way to get the C<last_insert_id>
50 without doing a C<SELECT MAX(col)>. This is done safely in a transaction
51 (locking the table.) See L</INSERTS WITH PLACEHOLDERS>.
53 A recommended L<connect_info|DBIx::Class::Storage::DBI/connect_info> setting:
55 on_connect_call => [['datetime_setup'], ['blob_setup', log_on_update => 0]]
64 my $no_bind_vars = __PACKAGE__ . '::NoBindVars';
66 if ($self->using_freetds) {
67 carp <<'EOF' unless $ENV{DBIC_SYBASE_FREETDS_NOWARN};
69 You are using FreeTDS with Sybase.
71 We will do our best to support this configuration, but please consider this
74 TEXT/IMAGE columns will definitely not work.
76 You are encouraged to recompile DBD::Sybase with the Sybase Open Client libraries
79 See perldoc DBIx::Class::Storage::DBI::Sybase::ASE for more details.
81 To turn off this warning set the DBIC_SYBASE_FREETDS_NOWARN environment
85 if (not $self->_typeless_placeholders_supported) {
86 if ($self->_placeholders_supported) {
90 $self->ensure_class_loaded($no_bind_vars);
91 bless $self, $no_bind_vars;
97 elsif (not $self->_get_dbh->{syb_dynamic_supported}) {
98 # not necessarily FreeTDS, but no placeholders nevertheless
99 $self->ensure_class_loaded($no_bind_vars);
100 bless $self, $no_bind_vars;
103 # this is highly unlikely, but we check just in case
104 elsif (not $self->_typeless_placeholders_supported) {
111 $self->_set_max_connect(256);
113 # create storage for insert/(update blob) transactions,
114 # unless this is that storage
115 return if $self->_is_extra_storage;
117 my $writer_storage = (ref $self)->new;
119 $writer_storage->_is_extra_storage(1);
120 $writer_storage->connect_info($self->connect_info);
121 $writer_storage->auto_cast($self->auto_cast);
123 $self->_writer_storage($writer_storage);
125 # create a bulk storage unless connect_info is a coderef
126 return if ref($self->_dbi_connect_info->[0]) eq 'CODE';
128 my $bulk_storage = (ref $self)->new;
130 $bulk_storage->_is_extra_storage(1);
131 $bulk_storage->_is_bulk_storage(1); # for special ->disconnect acrobatics
132 $bulk_storage->connect_info($self->connect_info);
135 $bulk_storage->_dbi_connect_info->[0] .= ';bulkLogin=1';
137 $self->_bulk_storage($bulk_storage);
140 for my $method (@also_proxy_to_extra_storages) {
142 no warnings 'redefine';
144 my $replaced = __PACKAGE__->can($method);
146 *{$method} = Sub::Name::subname $method => sub {
148 $self->_writer_storage->$replaced(@_) if $self->_writer_storage;
149 $self->_bulk_storage->$replaced(@_) if $self->_bulk_storage;
150 return $self->$replaced(@_);
157 # Even though we call $sth->finish for uses off the bulk API, there's still an
158 # "active statement" warning on disconnect, which we throw away here.
159 # This is due to the bug described in insert_bulk.
160 # Currently a noop because 'prepare' is used instead of 'prepare_cached'.
161 local $SIG{__WARN__} = sub {
162 warn $_[0] unless $_[0] =~ /active statement/i;
163 } if $self->_is_bulk_storage;
165 # so that next transaction gets a dbh
166 $self->_began_bulk_work(0) if $self->_is_bulk_storage;
171 # Set up session settings for Sybase databases for the connection.
173 # Make sure we have CHAINED mode turned on if AutoCommit is off in non-FreeTDS
174 # DBD::Sybase (since we don't know how DBD::Sybase was compiled.) If however
175 # we're using FreeTDS, CHAINED mode turns on an implicit transaction which we
176 # only want when AutoCommit is off.
178 # Also SET TEXTSIZE for FreeTDS because LongReadLen doesn't work.
179 sub _run_connection_actions {
182 if ($self->_is_bulk_storage) {
183 # this should be cleared on every reconnect
184 $self->_began_bulk_work(0);
188 if (not $self->using_freetds) {
189 $self->_dbh->{syb_chained_txn} = 1;
191 # based on LongReadLen in connect_info
194 if ($self->_dbh_autocommit) {
195 $self->_dbh->do('SET CHAINED OFF');
197 $self->_dbh->do('SET CHAINED ON');
201 $self->next::method(@_);
204 =head2 connect_call_blob_setup
208 on_connect_call => [ [ 'blob_setup', log_on_update => 0 ] ]
210 Does C<< $dbh->{syb_binary_images} = 1; >> to return C<IMAGE> data as raw binary
211 instead of as a hex string.
215 Also sets the C<log_on_update> value for blob write operations. The default is
216 C<1>, but C<0> is better if your database is configured for it.
219 L<DBD::Sybase/Handling_IMAGE/TEXT_data_with_syb_ct_get_data()/syb_ct_send_data()>.
223 sub connect_call_blob_setup {
226 my $dbh = $self->_dbh;
227 $dbh->{syb_binary_images} = 1;
229 $self->_blob_log_on_update($args{log_on_update})
230 if exists $args{log_on_update};
236 $type && $type =~ /(?:text|image|lob|bytea|binary|memo)/i;
240 my ($self, $source, $column) = @_;
242 return $self->_is_lob_type($source->column_info($column)->{data_type});
245 sub _prep_for_execute {
247 my ($op, $extra_bind, $ident, $args) = @_;
249 my ($sql, $bind) = $self->next::method (@_);
251 my $table = Scalar::Util::blessed($ident) ? $ident->from : $ident;
253 my $bind_info = $self->_resolve_column_info(
254 $ident, [map $_->[0], @{$bind}]
256 my $bound_identity_col = List::Util::first
257 { $bind_info->{$_}{is_auto_increment} }
260 my $identity_col = Scalar::Util::blessed($ident) &&
262 { $ident->column_info($_)->{is_auto_increment} }
266 if (($op eq 'insert' && $bound_identity_col) ||
267 ($op eq 'update' && exists $args->[0]{$identity_col})) {
269 $self->_set_table_identity_sql($op => $table, 'on'),
271 $self->_set_table_identity_sql($op => $table, 'off'),
275 if ($op eq 'insert' && (not $bound_identity_col) && $identity_col &&
276 (not $self->{insert_bulk})) {
279 $self->_fetch_identity_sql($ident, $identity_col);
282 return ($sql, $bind);
285 sub _set_table_identity_sql {
286 my ($self, $op, $table, $on_off) = @_;
288 return sprintf 'SET IDENTITY_%s %s %s',
289 uc($op), $self->sql_maker->_quote($table), uc($on_off);
292 # Stolen from SQLT, with some modifications. This is a makeshift
293 # solution before a sane type-mapping library is available, thus
294 # the 'our' for easy overrides.
295 our %TYPE_MAPPING = (
298 varchar => 'varchar',
299 varchar2 => 'varchar',
300 timestamp => 'datetime',
302 real => 'double precision',
305 tinyint => 'smallint',
306 float => 'double precision',
308 bigserial => 'numeric',
309 boolean => 'varchar',
313 sub _native_data_type {
314 my ($self, $type) = @_;
317 $type =~ s/\s* identity//x;
319 return uc($TYPE_MAPPING{$type} || $type);
322 sub _fetch_identity_sql {
323 my ($self, $source, $col) = @_;
325 return sprintf ("SELECT MAX(%s) FROM %s",
326 map { $self->sql_maker->_quote ($_) } ($col, $source->from)
334 my ($rv, $sth, @bind) = $self->dbh_do($self->can('_dbh_execute'), @_);
336 if ($op eq 'insert') {
337 $self->_identity($sth->fetchrow_array);
341 return wantarray ? ($rv, $sth, @bind) : $rv;
344 sub last_insert_id { shift->_identity }
346 # handles TEXT/IMAGE and transaction for last_insert_id
349 my ($source, $to_insert) = @_;
351 my $identity_col = (List::Util::first
352 { $source->column_info($_)->{is_auto_increment} }
353 $source->columns) || '';
355 # check for empty insert
356 # INSERT INTO foo DEFAULT VALUES -- does not work with Sybase
357 # try to insert explicit 'DEFAULT's instead (except for identity, timestamp
358 # and computed columns)
359 if (not %$to_insert) {
360 for my $col ($source->columns) {
361 next if $col eq $identity_col;
363 my $info = $source->column_info($col);
365 next if ref $info->{default_value} eq 'SCALAR'
366 || (exists $info->{data_type} && (not defined $info->{data_type}));
368 next if $info->{data_type} && $info->{data_type} =~ /^timestamp\z/i;
370 $to_insert->{$col} = \'DEFAULT';
374 my $blob_cols = $self->_remove_blob_cols($source, $to_insert);
376 # do we need the horrific SELECT MAX(COL) hack?
377 my $dumb_last_insert_id =
379 && (not exists $to_insert->{$identity_col})
380 && ($self->_identity_method||'') ne '@@IDENTITY';
382 my $next = $self->next::can;
384 # we are already in a transaction, or there are no blobs
385 # and we don't need the PK - just (try to) do it
386 if ($self->{transaction_depth}
387 || (!$blob_cols && !$dumb_last_insert_id)
389 return $self->_insert (
390 $next, $source, $to_insert, $blob_cols, $identity_col
394 # otherwise use the _writer_storage to do the insert+transaction on another
396 my $guard = $self->_writer_storage->txn_scope_guard;
398 my $updated_cols = $self->_writer_storage->_insert (
399 $next, $source, $to_insert, $blob_cols, $identity_col
402 $self->_identity($self->_writer_storage->_identity);
406 return $updated_cols;
410 my ($self, $next, $source, $to_insert, $blob_cols, $identity_col) = @_;
412 my $updated_cols = $self->$next ($source, $to_insert);
416 ($identity_col => $self->last_insert_id($source, $identity_col)) : ()),
421 $self->_insert_blobs ($source, $blob_cols, $final_row) if $blob_cols;
423 return $updated_cols;
428 my ($source, $fields, $where, @rest) = @_;
430 my $wantarray = wantarray;
432 my $blob_cols = $self->_remove_blob_cols($source, $fields);
434 my $table = $source->name;
436 my $identity_col = List::Util::first
437 { $source->column_info($_)->{is_auto_increment} }
440 my $is_identity_update = $identity_col && defined $fields->{$identity_col};
442 return $self->next::method(@_) unless $blob_cols;
444 # If there are any blobs in $where, Sybase will return a descriptive error
446 # XXX blobs can still be used with a LIKE query, and this should be handled.
448 # update+blob update(s) done atomically on separate connection
449 $self = $self->_writer_storage;
451 my $guard = $self->txn_scope_guard;
453 # First update the blob columns to be updated to '' (taken from $fields, where
454 # it is originally put by _remove_blob_cols .)
455 my %blobs_to_empty = map { ($_ => delete $fields->{$_}) } keys %$blob_cols;
457 # We can't only update NULL blobs, because blobs cannot be in the WHERE clause.
459 $self->next::method($source, \%blobs_to_empty, $where, @rest);
461 # Now update the blobs before the other columns in case the update of other
462 # columns makes the search condition invalid.
463 $self->_update_blobs($source, $blob_cols, $where);
468 @res = $self->next::method(@_);
470 elsif (defined $wantarray) {
471 $res[0] = $self->next::method(@_);
474 $self->next::method(@_);
480 return $wantarray ? @res : $res[0];
485 my ($source, $cols, $data) = @_;
487 my $identity_col = List::Util::first
488 { $source->column_info($_)->{is_auto_increment} }
491 my $is_identity_insert = (List::Util::first
492 { $_ eq $identity_col }
496 my @source_columns = $source->columns;
499 $self->_bulk_storage &&
500 $self->_get_dbh->{syb_has_blk};
502 if ((not $use_bulk_api)
504 (ref($self->_dbi_connect_info->[0]) eq 'CODE')
506 (not $self->_bulk_disabled_due_to_coderef_connect_info_warned)) {
508 Bulk API support disabled due to use of a CODEREF connect_info. Reverting to
509 regular array inserts.
511 $self->_bulk_disabled_due_to_coderef_connect_info_warned(1);
514 if (not $use_bulk_api) {
515 my $blob_cols = $self->_remove_blob_cols_array($source, $cols, $data);
517 # _execute_array uses a txn anyway, but it ends too early in case we need to
518 # select max(col) to get the identity for inserting blobs.
519 ($self, my $guard) = $self->{transaction_depth} == 0 ?
520 ($self->_writer_storage, $self->_writer_storage->txn_scope_guard)
524 local $self->{insert_bulk} = 1;
526 $self->next::method(@_);
529 if ($is_identity_insert) {
530 $self->_insert_blobs_array ($source, $blob_cols, $cols, $data);
533 my @cols_with_identities = (@$cols, $identity_col);
535 ## calculate identities
536 # XXX This assumes identities always increase by 1, which may or may not
538 my ($last_identity) =
539 $self->_dbh->selectrow_array (
540 $self->_fetch_identity_sql($source, $identity_col)
542 my @identities = (($last_identity - @$data + 1) .. $last_identity);
544 my @data_with_identities = map [@$_, shift @identities], @$data;
546 $self->_insert_blobs_array (
547 $source, $blob_cols, \@cols_with_identities, \@data_with_identities
552 $guard->commit if $guard;
557 # otherwise, use the bulk API
559 # rearrange @$data so that columns are in database order
561 @orig_idx{@$cols} = 0..$#$cols;
564 @new_idx{@source_columns} = 0..$#source_columns;
567 for my $datum (@$data) {
569 for my $col (@source_columns) {
570 # identity data will be 'undef' if not $is_identity_insert
571 # columns with defaults will also be 'undef'
572 $new_datum->[ $new_idx{$col} ] =
573 exists $orig_idx{$col} ? $datum->[ $orig_idx{$col} ] : undef;
575 push @new_data, $new_datum;
578 # bcp identity index is 1-based
579 my $identity_idx = exists $new_idx{$identity_col} ?
580 $new_idx{$identity_col} + 1 : 0;
582 ## Set a client-side conversion error handler, straight from DBD::Sybase docs.
583 # This ignores any data conversion errors detected by the client side libs, as
584 # they are usually harmless.
585 my $orig_cslib_cb = DBD::Sybase::set_cslib_cb(
586 Sub::Name::subname insert_bulk => sub {
587 my ($layer, $origin, $severity, $errno, $errmsg, $osmsg, $blkmsg) = @_;
589 return 1 if $errno == 36;
592 "Layer: $layer, Origin: $origin, Severity: $severity, Error: $errno" .
593 ($errmsg ? "\n$errmsg" : '') .
594 ($osmsg ? "\n$osmsg" : '') .
595 ($blkmsg ? "\n$blkmsg" : '');
602 my $bulk = $self->_bulk_storage;
604 my $guard = $bulk->txn_scope_guard;
606 ## XXX get this to work instead of our own $sth
607 ## will require SQLA or *Hacks changes for ordered columns
608 # $bulk->next::method($source, \@source_columns, \@new_data, {
609 # syb_bcp_attribs => {
610 # identity_flag => $is_identity_insert,
611 # identity_column => $identity_idx,
614 my $sql = 'INSERT INTO ' .
615 $bulk->sql_maker->_quote($source->name) . ' (' .
616 # colname list is ignored for BCP, but does no harm
617 (join ', ', map $bulk->sql_maker->_quote($_), @source_columns) . ') '.
618 ' VALUES ('. (join ', ', ('?') x @source_columns) . ')';
620 ## XXX there's a bug in the DBD::Sybase bulk support that makes $sth->finish for
621 ## a prepare_cached statement ineffective. Replace with ->sth when fixed, or
622 ## better yet the version above. Should be fixed in DBD::Sybase .
623 my $sth = $bulk->_get_dbh->prepare($sql,
627 identity_flag => $is_identity_insert,
628 identity_column => $identity_idx,
635 map [ $_, $idx++ ], @source_columns;
638 $self->_execute_array(
639 $source, $sth, \@bind, \@source_columns, \@new_data, sub {
644 $bulk->_query_end($sql);
649 DBD::Sybase::set_cslib_cb($orig_cslib_cb);
651 if ($exception =~ /-Y option/) {
654 Sybase bulk API operation failed due to character set incompatibility, reverting
655 to regular array inserts:
657 *** Try unsetting the LANG environment variable.
661 $self->_bulk_storage(undef);
666 # rollback makes the bulkLogin connection unusable
667 $self->_bulk_storage->disconnect;
668 $self->throw_exception($exception);
672 sub _dbh_execute_array {
673 my ($self, $sth, $tuple_status, $cb) = @_;
675 my $rv = $self->next::method($sth, $tuple_status);
681 # Make sure blobs are not bound as placeholders, and return any non-empty ones
683 sub _remove_blob_cols {
684 my ($self, $source, $fields) = @_;
688 for my $col (keys %$fields) {
689 if ($self->_is_lob_column($source, $col)) {
690 my $blob_val = delete $fields->{$col};
691 if (not defined $blob_val) {
692 $fields->{$col} = \'NULL';
695 $fields->{$col} = \"''";
696 $blob_cols{$col} = $blob_val unless $blob_val eq '';
701 return %blob_cols ? \%blob_cols : undef;
704 # same for insert_bulk
705 sub _remove_blob_cols_array {
706 my ($self, $source, $cols, $data) = @_;
710 for my $i (0..$#$cols) {
711 my $col = $cols->[$i];
713 if ($self->_is_lob_column($source, $col)) {
714 for my $j (0..$#$data) {
715 my $blob_val = delete $data->[$j][$i];
716 if (not defined $blob_val) {
717 $data->[$j][$i] = \'NULL';
720 $data->[$j][$i] = \"''";
721 $blob_cols[$j][$i] = $blob_val
722 unless $blob_val eq '';
728 return @blob_cols ? \@blob_cols : undef;
732 my ($self, $source, $blob_cols, $where) = @_;
734 my @primary_cols = eval { $source->_pri_cols };
735 $self->throw_exception("Cannot update TEXT/IMAGE column(s): $@")
738 # check if we're updating a single row by PK
739 my $pk_cols_in_where = 0;
740 for my $col (@primary_cols) {
741 $pk_cols_in_where++ if defined $where->{$col};
745 if ($pk_cols_in_where == @primary_cols) {
747 @row_to_update{@primary_cols} = @{$where}{@primary_cols};
748 @rows = \%row_to_update;
750 my $cursor = $self->select ($source, \@primary_cols, $where, {});
752 my %row; @row{@primary_cols} = @$_; \%row
756 for my $row (@rows) {
757 $self->_insert_blobs($source, $blob_cols, $row);
762 my ($self, $source, $blob_cols, $row) = @_;
763 my $dbh = $self->_get_dbh;
765 my $table = $source->name;
768 my @primary_cols = eval { $source->_pri_cols} ;
769 $self->throw_exception("Cannot update TEXT/IMAGE column(s): $@")
772 $self->throw_exception('Cannot update TEXT/IMAGE column(s) without primary key values')
773 if ((grep { defined $row{$_} } @primary_cols) != @primary_cols);
775 for my $col (keys %$blob_cols) {
776 my $blob = $blob_cols->{$col};
778 my %where = map { ($_, $row{$_}) } @primary_cols;
780 my $cursor = $self->select ($source, [$col], \%where, {});
782 my $sth = $cursor->sth;
786 $self->throw_exception(
787 "Could not find row in table '$table' for blob update:\n"
788 . Data::Dumper::Concise::Dumper (\%where)
794 $sth->func('CS_GET', 1, 'ct_data_info') or die $sth->errstr;
797 $sth->func('ct_prepare_send') or die $sth->errstr;
799 my $log_on_update = $self->_blob_log_on_update;
800 $log_on_update = 1 if not defined $log_on_update;
802 $sth->func('CS_SET', 1, {
803 total_txtlen => length($blob),
804 log_on_update => $log_on_update
805 }, 'ct_data_info') or die $sth->errstr;
807 $sth->func($blob, length($blob), 'ct_send_data') or die $sth->errstr;
809 $sth->func('ct_finish_send') or die $sth->errstr;
812 $sth->finish if $sth;
814 if ($self->using_freetds) {
815 $self->throw_exception (
816 'TEXT/IMAGE operation failed, probably because you are using FreeTDS: '
820 $self->throw_exception($exception);
826 sub _insert_blobs_array {
827 my ($self, $source, $blob_cols, $cols, $data) = @_;
829 for my $i (0..$#$data) {
830 my $datum = $data->[$i];
833 @row{ @$cols } = @$datum;
836 for my $j (0..$#$cols) {
837 if (exists $blob_cols->[$i][$j]) {
838 $blob_vals{ $cols->[$j] } = $blob_cols->[$i][$j];
842 $self->_insert_blobs ($source, \%blob_vals, \%row);
846 =head2 connect_call_datetime_setup
850 on_connect_call => 'datetime_setup'
852 In L<connect_info|DBIx::Class::Storage::DBI/connect_info> to set:
854 $dbh->syb_date_fmt('ISO_strict'); # output fmt: 2004-08-21T14:36:48.080Z
855 $dbh->do('set dateformat mdy'); # input fmt: 08/13/1979 18:08:55.080
857 On connection for use with L<DBIx::Class::InflateColumn::DateTime>, using
858 L<DateTime::Format::Sybase>, which you will need to install.
860 This works for both C<DATETIME> and C<SMALLDATETIME> columns, although
861 C<SMALLDATETIME> columns only have minute precision.
866 my $old_dbd_warned = 0;
868 sub connect_call_datetime_setup {
870 my $dbh = $self->_get_dbh;
872 if ($dbh->can('syb_date_fmt')) {
873 # amazingly, this works with FreeTDS
874 $dbh->syb_date_fmt('ISO_strict');
875 } elsif (not $old_dbd_warned) {
876 carp "Your DBD::Sybase is too old to support ".
877 "DBIx::Class::InflateColumn::DateTime, please upgrade!";
881 $dbh->do('SET DATEFORMAT mdy');
887 sub datetime_parser_type { "DateTime::Format::Sybase" }
889 # ->begin_work and such have no effect with FreeTDS but we run them anyway to
890 # let the DBD keep any state it needs to.
892 # If they ever do start working, the extra statements will do no harm (because
893 # Sybase supports nested transactions.)
895 sub _dbh_begin_work {
898 # bulkLogin=1 connections are always in a transaction, and can only call BEGIN
899 # TRAN once. However, we need to make sure there's a $dbh.
900 return if $self->_is_bulk_storage && $self->_dbh && $self->_began_bulk_work;
902 $self->next::method(@_);
904 if ($self->using_freetds) {
905 $self->_get_dbh->do('BEGIN TRAN');
908 $self->_began_bulk_work(1) if $self->_is_bulk_storage;
913 if ($self->using_freetds) {
914 $self->_dbh->do('COMMIT');
916 return $self->next::method(@_);
921 if ($self->using_freetds) {
922 $self->_dbh->do('ROLLBACK');
924 return $self->next::method(@_);
927 # savepoint support using ASE syntax
930 my ($self, $name) = @_;
932 $self->_get_dbh->do("SAVE TRANSACTION $name");
935 # A new SAVE TRANSACTION with the same name releases the previous one.
936 sub _svp_release { 1 }
939 my ($self, $name) = @_;
941 $self->_get_dbh->do("ROLLBACK TRANSACTION $name");
946 =head1 Schema::Loader Support
948 As of version C<0.05000>, L<DBIx::Class::Schema::Loader> should work well with
949 most (if not all) versions of Sybase ASE.
953 This driver supports L<DBD::Sybase> compiled against FreeTDS
954 (L<http://www.freetds.org/>) to the best of our ability, however it is
955 recommended that you recompile L<DBD::Sybase> against the Sybase Open Client
956 libraries. They are a part of the Sybase ASE distribution:
958 The Open Client FAQ is here:
959 L<http://www.isug.com/Sybase_FAQ/ASE/section7.html>.
961 Sybase ASE for Linux (which comes with the Open Client libraries) may be
962 downloaded here: L<http://response.sybase.com/forms/ASE_Linux_Download>.
964 To see if you're using FreeTDS check C<< $schema->storage->using_freetds >>, or run:
966 perl -MDBI -le 'my $dbh = DBI->connect($dsn, $user, $pass); print $dbh->{syb_oc_version}'
968 Some versions of the libraries involved will not support placeholders, in which
969 case the storage will be reblessed to
970 L<DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars>.
972 In some configurations, placeholders will work but will throw implicit type
973 conversion errors for anything that's not expecting a string. In such a case,
974 the C<auto_cast> option from L<DBIx::Class::Storage::DBI::AutoCast> is
975 automatically set, which you may enable on connection with
976 L<DBIx::Class::Storage::DBI::AutoCast/connect_call_set_auto_cast>. The type info
977 for the C<CAST>s is taken from the L<DBIx::Class::ResultSource/data_type>
978 definitions in your Result classes, and are mapped to a Sybase type (if it isn't
979 already) using a mapping based on L<SQL::Translator>.
981 In other configurations, placeholders will work just as they do with the Sybase
982 Open Client libraries.
984 Inserts or updates of TEXT/IMAGE columns will B<NOT> work with FreeTDS.
986 =head1 INSERTS WITH PLACEHOLDERS
988 With placeholders enabled, inserts are done in a transaction so that there are
989 no concurrency issues with getting the inserted identity value using
990 C<SELECT MAX(col)>, which is the only way to get the C<IDENTITY> value in this
993 In addition, they are done on a separate connection so that it's possible to
994 have active cursors when doing an insert.
996 When using C<DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars> transactions
997 are disabled, as there are no concurrency issues with C<SELECT @@IDENTITY> as
998 it's a session variable.
1002 Due to limitations of the TDS protocol, L<DBD::Sybase>, or both, you cannot
1003 begin a transaction while there are active cursors, nor can you use multiple
1004 active cursors within a transaction. An active cursor is, for example, a
1005 L<ResultSet|DBIx::Class::ResultSet> that has been executed using C<next> or
1006 C<first> but has not been exhausted or L<reset|DBIx::Class::ResultSet/reset>.
1008 For example, this will not work:
1010 $schema->txn_do(sub {
1011 my $rs = $schema->resultset('Book');
1012 while (my $row = $rs->next) {
1013 $schema->resultset('MetaData')->create({
1014 book_id => $row->id,
1022 my $first_row = $large_rs->first;
1023 $schema->txn_do(sub { ... });
1025 Transactions done for inserts in C<AutoCommit> mode when placeholders are in use
1026 are not affected, as they are done on an extra database handle.
1032 =item * use L<DBIx::Class::Storage::DBI::Replicated>
1034 =item * L<connect|DBIx::Class::Schema/connect> another L<Schema|DBIx::Class::Schema>
1036 =item * load the data from your cursor with L<DBIx::Class::ResultSet/all>
1040 =head1 MAXIMUM CONNECTIONS
1042 The TDS protocol makes separate connections to the server for active statements
1043 in the background. By default the number of such connections is limited to 25,
1044 on both the client side and the server side.
1046 This is a bit too low for a complex L<DBIx::Class> application, so on connection
1047 the client side setting is set to C<256> (see L<DBD::Sybase/maxConnect>.) You
1048 can override it to whatever setting you like in the DSN.
1051 L<http://infocenter.sybase.com/help/index.jsp?topic=/com.sybase.help.ase_15.0.sag1/html/sag1/sag1272.htm>
1052 for information on changing the setting on the server side.
1056 See L</connect_call_datetime_setup> to setup date formats
1057 for L<DBIx::Class::InflateColumn::DateTime>.
1059 =head1 TEXT/IMAGE COLUMNS
1061 L<DBD::Sybase> compiled with FreeTDS will B<NOT> allow you to insert or update
1062 C<TEXT/IMAGE> columns.
1064 Setting C<< $dbh->{LongReadLen} >> will also not work with FreeTDS use either:
1066 $schema->storage->dbh->do("SET TEXTSIZE $bytes");
1070 $schema->storage->set_textsize($bytes);
1074 However, the C<LongReadLen> you pass in
1075 L<connect_info|DBIx::Class::Storage::DBI/connect_info> is used to execute the
1076 equivalent C<SET TEXTSIZE> command on connection.
1078 See L</connect_call_blob_setup> for a
1079 L<connect_info|DBIx::Class::Storage::DBI/connect_info> setting you need to work
1080 with C<IMAGE> columns.
1084 The experimental L<DBD::Sybase> Bulk API support is used for
1085 L<populate|DBIx::Class::ResultSet/populate> in B<void> context, in a transaction
1086 on a separate connection.
1088 To use this feature effectively, use a large number of rows for each
1089 L<populate|DBIx::Class::ResultSet/populate> call, eg.:
1091 while (my $rows = $data_source->get_100_rows()) {
1092 $rs->populate($rows);
1095 B<NOTE:> the L<add_columns|DBIx::Class::ResultSource/add_columns>
1096 calls in your C<Result> classes B<must> list columns in database order for this
1097 to work. Also, you may have to unset the C<LANG> environment variable before
1098 loading your app, if it doesn't match the character set of your database.
1100 When inserting IMAGE columns using this method, you'll need to use
1101 L</connect_call_blob_setup> as well.
1103 =head1 COMPUTED COLUMNS
1105 If you have columns such as:
1107 created_dtm AS getdate()
1109 represent them in your Result classes as:
1113 default_value => \'getdate()',
1117 The C<data_type> must exist and must be C<undef>. Then empty inserts will work
1118 on tables with such columns.
1120 =head1 TIMESTAMP COLUMNS
1122 C<timestamp> columns in Sybase ASE are not really timestamps, see:
1123 L<http://dba.fyicenter.com/Interview-Questions/SYBASE/The_timestamp_datatype_in_Sybase_.html>.
1125 They should be defined in your Result classes as:
1128 data_type => 'timestamp',
1130 inflate_datetime => 0,
1133 The C<<inflate_datetime => 0>> is necessary if you use
1134 L<DBIx::Class::InflateColumn::DateTime>, and most people do, and still want to
1135 be able to read these values.
1137 The values will come back as hexadecimal.
1145 Transitions to AutoCommit=0 (starting a transaction) mode by exhausting
1146 any active cursors, using eager cursors.
1150 Real limits and limited counts using stored procedures deployed on startup.
1154 Adaptive Server Anywhere (ASA) support, with possible SQLA::Limit support.
1158 Blob update with a LIKE query on a blob, without invalidating the WHERE condition.
1162 bulk_insert using prepare_cached (see comments.)
1168 See L<DBIx::Class/CONTRIBUTORS>.
1172 You may distribute this code under the same terms as Perl itself.