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();
19 __PACKAGE__->mk_group_accessors('simple' =>
20 qw/_identity _blob_log_on_update _writer_storage _is_extra_storage
21 _bulk_storage _is_bulk_storage _began_bulk_work
22 _bulk_disabled_due_to_coderef_connect_info_warned
26 my @also_proxy_to_extra_storages = qw/
27 connect_call_set_auto_cast auto_cast connect_call_blob_setup
28 connect_call_datetime_setup
30 disconnect _connect_info _sql_maker _sql_maker_opts disable_sth_caching
31 auto_savepoint unsafe cursor_class debug debugobj schema
36 DBIx::Class::Storage::DBI::Sybase::ASE - Sybase ASE SQL Server support for
41 This subclass supports L<DBD::Sybase> for real (non-Microsoft) Sybase databases.
45 If your version of Sybase does not support placeholders, then your storage will
46 be reblessed to L<DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars>.
47 You can also enable that driver explicitly, see the documentation for more
50 With this driver there is unfortunately no way to get the C<last_insert_id>
51 without doing a C<SELECT MAX(col)>. This is done safely in a transaction
52 (locking the table.) See L</INSERTS WITH PLACEHOLDERS>.
54 A recommended L<connect_info|DBIx::Class::Storage::DBI/connect_info> setting:
56 on_connect_call => [['datetime_setup'], ['blob_setup', log_on_update => 0]]
65 my $no_bind_vars = __PACKAGE__ . '::NoBindVars';
67 if ($self->using_freetds) {
68 carp <<'EOF' unless $ENV{DBIC_SYBASE_FREETDS_NOWARN};
70 You are using FreeTDS with Sybase.
72 We will do our best to support this configuration, but please consider this
75 TEXT/IMAGE columns will definitely not work.
77 You are encouraged to recompile DBD::Sybase with the Sybase Open Client libraries
80 See perldoc DBIx::Class::Storage::DBI::Sybase::ASE for more details.
82 To turn off this warning set the DBIC_SYBASE_FREETDS_NOWARN environment
86 if (not $self->_typeless_placeholders_supported) {
87 if ($self->_placeholders_supported) {
91 $self->ensure_class_loaded($no_bind_vars);
92 bless $self, $no_bind_vars;
98 elsif (not $self->_get_dbh->{syb_dynamic_supported}) {
99 # not necessarily FreeTDS, but no placeholders nevertheless
100 $self->ensure_class_loaded($no_bind_vars);
101 bless $self, $no_bind_vars;
104 # this is highly unlikely, but we check just in case
105 elsif (not $self->_typeless_placeholders_supported) {
112 $self->_set_max_connect(256);
114 # create storage for insert/(update blob) transactions,
115 # unless this is that storage
116 return if $self->_is_extra_storage;
118 my $writer_storage = (ref $self)->new;
120 $writer_storage->_is_extra_storage(1);
121 $writer_storage->connect_info($self->connect_info);
122 $writer_storage->auto_cast($self->auto_cast);
124 $self->_writer_storage($writer_storage);
126 # create a bulk storage unless connect_info is a coderef
127 return if ref($self->_dbi_connect_info->[0]) eq 'CODE';
129 my $bulk_storage = (ref $self)->new;
131 $bulk_storage->_is_extra_storage(1);
132 $bulk_storage->_is_bulk_storage(1); # for special ->disconnect acrobatics
133 $bulk_storage->connect_info($self->connect_info);
136 $bulk_storage->_dbi_connect_info->[0] .= ';bulkLogin=1';
138 $self->_bulk_storage($bulk_storage);
141 for my $method (@also_proxy_to_extra_storages) {
143 no warnings 'redefine';
145 my $replaced = __PACKAGE__->can($method);
147 *{$method} = Sub::Name::subname $method => sub {
149 $self->_writer_storage->$replaced(@_) if $self->_writer_storage;
150 $self->_bulk_storage->$replaced(@_) if $self->_bulk_storage;
151 return $self->$replaced(@_);
158 # Even though we call $sth->finish for uses off the bulk API, there's still an
159 # "active statement" warning on disconnect, which we throw away here.
160 # This is due to the bug described in insert_bulk.
161 # Currently a noop because 'prepare' is used instead of 'prepare_cached'.
162 local $SIG{__WARN__} = sub {
163 warn $_[0] unless $_[0] =~ /active statement/i;
164 } if $self->_is_bulk_storage;
166 # so that next transaction gets a dbh
167 $self->_began_bulk_work(0) if $self->_is_bulk_storage;
172 # Set up session settings for Sybase databases for the connection.
174 # Make sure we have CHAINED mode turned on if AutoCommit is off in non-FreeTDS
175 # DBD::Sybase (since we don't know how DBD::Sybase was compiled.) If however
176 # we're using FreeTDS, CHAINED mode turns on an implicit transaction which we
177 # only want when AutoCommit is off.
179 # Also SET TEXTSIZE for FreeTDS because LongReadLen doesn't work.
180 sub _run_connection_actions {
183 if ($self->_is_bulk_storage) {
184 # this should be cleared on every reconnect
185 $self->_began_bulk_work(0);
189 if (not $self->using_freetds) {
190 $self->_dbh->{syb_chained_txn} = 1;
192 # based on LongReadLen in connect_info
195 if ($self->_dbh_autocommit) {
196 $self->_dbh->do('SET CHAINED OFF');
198 $self->_dbh->do('SET CHAINED ON');
202 $self->next::method(@_);
205 =head2 connect_call_blob_setup
209 on_connect_call => [ [ 'blob_setup', log_on_update => 0 ] ]
211 Does C<< $dbh->{syb_binary_images} = 1; >> to return C<IMAGE> data as raw binary
212 instead of as a hex string.
216 Also sets the C<log_on_update> value for blob write operations. The default is
217 C<1>, but C<0> is better if your database is configured for it.
220 L<DBD::Sybase/Handling_IMAGE/TEXT_data_with_syb_ct_get_data()/syb_ct_send_data()>.
224 sub connect_call_blob_setup {
227 my $dbh = $self->_dbh;
228 $dbh->{syb_binary_images} = 1;
230 $self->_blob_log_on_update($args{log_on_update})
231 if exists $args{log_on_update};
237 $type && $type =~ /(?:text|image|lob|bytea|binary|memo)/i;
241 my ($self, $source, $column) = @_;
243 return $self->_is_lob_type($source->column_info($column)->{data_type});
246 sub _prep_for_execute {
248 my ($op, $extra_bind, $ident, $args) = @_;
250 my ($sql, $bind) = $self->next::method (@_);
252 my $table = Scalar::Util::blessed($ident) ? $ident->from : $ident;
254 my $bind_info = $self->_resolve_column_info(
255 $ident, [map $_->[0], @{$bind}]
257 my $bound_identity_col = List::Util::first
258 { $bind_info->{$_}{is_auto_increment} }
261 my $identity_col = Scalar::Util::blessed($ident) &&
263 { $ident->column_info($_)->{is_auto_increment} }
267 if (($op eq 'insert' && $bound_identity_col) ||
268 ($op eq 'update' && exists $args->[0]{$identity_col})) {
270 $self->_set_table_identity_sql($op => $table, 'on'),
272 $self->_set_table_identity_sql($op => $table, 'off'),
276 if ($op eq 'insert' && (not $bound_identity_col) && $identity_col &&
277 (not $self->{insert_bulk})) {
280 $self->_fetch_identity_sql($ident, $identity_col);
283 return ($sql, $bind);
286 sub _set_table_identity_sql {
287 my ($self, $op, $table, $on_off) = @_;
289 return sprintf 'SET IDENTITY_%s %s %s',
290 uc($op), $self->sql_maker->_quote($table), uc($on_off);
293 # Stolen from SQLT, with some modifications. This is a makeshift
294 # solution before a sane type-mapping library is available, thus
295 # the 'our' for easy overrides.
296 our %TYPE_MAPPING = (
299 varchar => 'varchar',
300 varchar2 => 'varchar',
301 timestamp => 'datetime',
303 real => 'double precision',
306 tinyint => 'smallint',
307 float => 'double precision',
309 bigserial => 'numeric',
310 boolean => 'varchar',
314 sub _native_data_type {
315 my ($self, $type) = @_;
318 $type =~ s/\s* identity//x;
320 return uc($TYPE_MAPPING{$type} || $type);
323 sub _fetch_identity_sql {
324 my ($self, $source, $col) = @_;
326 return sprintf ("SELECT MAX(%s) FROM %s",
327 map { $self->sql_maker->_quote ($_) } ($col, $source->from)
335 my ($rv, $sth, @bind) = $self->dbh_do($self->can('_dbh_execute'), @_);
337 if ($op eq 'insert') {
338 $self->_identity($sth->fetchrow_array);
342 return wantarray ? ($rv, $sth, @bind) : $rv;
345 sub last_insert_id { shift->_identity }
347 # handles TEXT/IMAGE and transaction for last_insert_id
350 my ($source, $to_insert) = @_;
352 my $identity_col = (List::Util::first
353 { $source->column_info($_)->{is_auto_increment} }
354 $source->columns) || '';
356 # check for empty insert
357 # INSERT INTO foo DEFAULT VALUES -- does not work with Sybase
358 # try to insert explicit 'DEFAULT's instead (except for identity, timestamp
359 # and computed columns)
360 if (not %$to_insert) {
361 for my $col ($source->columns) {
362 next if $col eq $identity_col;
364 my $info = $source->column_info($col);
366 next if ref $info->{default_value} eq 'SCALAR'
367 || (exists $info->{data_type} && (not defined $info->{data_type}));
369 next if $info->{data_type} && $info->{data_type} =~ /^timestamp\z/i;
371 $to_insert->{$col} = \'DEFAULT';
375 my $blob_cols = $self->_remove_blob_cols($source, $to_insert);
377 # do we need the horrific SELECT MAX(COL) hack?
378 my $dumb_last_insert_id =
380 && (not exists $to_insert->{$identity_col})
381 && ($self->_identity_method||'') ne '@@IDENTITY';
383 my $next = $self->next::can;
385 # we are already in a transaction, or there are no blobs
386 # and we don't need the PK - just (try to) do it
387 if ($self->{transaction_depth}
388 || (!$blob_cols && !$dumb_last_insert_id)
390 return $self->_insert (
391 $next, $source, $to_insert, $blob_cols, $identity_col
395 # otherwise use the _writer_storage to do the insert+transaction on another
397 my $guard = $self->_writer_storage->txn_scope_guard;
399 my $updated_cols = $self->_writer_storage->_insert (
400 $next, $source, $to_insert, $blob_cols, $identity_col
403 $self->_identity($self->_writer_storage->_identity);
407 return $updated_cols;
411 my ($self, $next, $source, $to_insert, $blob_cols, $identity_col) = @_;
413 my $updated_cols = $self->$next ($source, $to_insert);
417 ($identity_col => $self->last_insert_id($source, $identity_col)) : ()),
422 $self->_insert_blobs ($source, $blob_cols, $final_row) if $blob_cols;
424 return $updated_cols;
429 my ($source, $fields, $where, @rest) = @_;
431 my $wantarray = wantarray;
433 my $blob_cols = $self->_remove_blob_cols($source, $fields);
435 my $table = $source->name;
437 my $identity_col = List::Util::first
438 { $source->column_info($_)->{is_auto_increment} }
441 my $is_identity_update = $identity_col && defined $fields->{$identity_col};
443 return $self->next::method(@_) unless $blob_cols;
445 # If there are any blobs in $where, Sybase will return a descriptive error
447 # XXX blobs can still be used with a LIKE query, and this should be handled.
449 # update+blob update(s) done atomically on separate connection
450 $self = $self->_writer_storage;
452 my $guard = $self->txn_scope_guard;
454 # First update the blob columns to be updated to '' (taken from $fields, where
455 # it is originally put by _remove_blob_cols .)
456 my %blobs_to_empty = map { ($_ => delete $fields->{$_}) } keys %$blob_cols;
458 # We can't only update NULL blobs, because blobs cannot be in the WHERE clause.
460 $self->next::method($source, \%blobs_to_empty, $where, @rest);
462 # Now update the blobs before the other columns in case the update of other
463 # columns makes the search condition invalid.
464 $self->_update_blobs($source, $blob_cols, $where);
469 @res = $self->next::method(@_);
471 elsif (defined $wantarray) {
472 $res[0] = $self->next::method(@_);
475 $self->next::method(@_);
481 return $wantarray ? @res : $res[0];
486 my ($source, $cols, $data) = @_;
488 my $identity_col = List::Util::first
489 { $source->column_info($_)->{is_auto_increment} }
492 my $is_identity_insert = (List::Util::first
493 { $_ eq $identity_col }
497 my @source_columns = $source->columns;
500 $self->_bulk_storage &&
501 $self->_get_dbh->{syb_has_blk};
503 if ((not $use_bulk_api)
505 (ref($self->_dbi_connect_info->[0]) eq 'CODE')
507 (not $self->_bulk_disabled_due_to_coderef_connect_info_warned)) {
509 Bulk API support disabled due to use of a CODEREF connect_info. Reverting to
510 regular array inserts.
512 $self->_bulk_disabled_due_to_coderef_connect_info_warned(1);
515 if (not $use_bulk_api) {
516 my $blob_cols = $self->_remove_blob_cols_array($source, $cols, $data);
518 # _execute_array uses a txn anyway, but it ends too early in case we need to
519 # select max(col) to get the identity for inserting blobs.
520 ($self, my $guard) = $self->{transaction_depth} == 0 ?
521 ($self->_writer_storage, $self->_writer_storage->txn_scope_guard)
525 local $self->{insert_bulk} = 1;
527 $self->next::method(@_);
530 if ($is_identity_insert) {
531 $self->_insert_blobs_array ($source, $blob_cols, $cols, $data);
534 my @cols_with_identities = (@$cols, $identity_col);
536 ## calculate identities
537 # XXX This assumes identities always increase by 1, which may or may not
539 my ($last_identity) =
540 $self->_dbh->selectrow_array (
541 $self->_fetch_identity_sql($source, $identity_col)
543 my @identities = (($last_identity - @$data + 1) .. $last_identity);
545 my @data_with_identities = map [@$_, shift @identities], @$data;
547 $self->_insert_blobs_array (
548 $source, $blob_cols, \@cols_with_identities, \@data_with_identities
553 $guard->commit if $guard;
558 # otherwise, use the bulk API
560 # rearrange @$data so that columns are in database order
562 @orig_idx{@$cols} = 0..$#$cols;
565 @new_idx{@source_columns} = 0..$#source_columns;
568 for my $datum (@$data) {
570 for my $col (@source_columns) {
571 # identity data will be 'undef' if not $is_identity_insert
572 # columns with defaults will also be 'undef'
573 $new_datum->[ $new_idx{$col} ] =
574 exists $orig_idx{$col} ? $datum->[ $orig_idx{$col} ] : undef;
576 push @new_data, $new_datum;
579 # bcp identity index is 1-based
580 my $identity_idx = exists $new_idx{$identity_col} ?
581 $new_idx{$identity_col} + 1 : 0;
583 ## Set a client-side conversion error handler, straight from DBD::Sybase docs.
584 # This ignores any data conversion errors detected by the client side libs, as
585 # they are usually harmless.
586 my $orig_cslib_cb = DBD::Sybase::set_cslib_cb(
587 Sub::Name::subname insert_bulk => sub {
588 my ($layer, $origin, $severity, $errno, $errmsg, $osmsg, $blkmsg) = @_;
590 return 1 if $errno == 36;
593 "Layer: $layer, Origin: $origin, Severity: $severity, Error: $errno" .
594 ($errmsg ? "\n$errmsg" : '') .
595 ($osmsg ? "\n$osmsg" : '') .
596 ($blkmsg ? "\n$blkmsg" : '');
603 my $bulk = $self->_bulk_storage;
605 my $guard = $bulk->txn_scope_guard;
607 ## XXX get this to work instead of our own $sth
608 ## will require SQLA or *Hacks changes for ordered columns
609 # $bulk->next::method($source, \@source_columns, \@new_data, {
610 # syb_bcp_attribs => {
611 # identity_flag => $is_identity_insert,
612 # identity_column => $identity_idx,
615 my $sql = 'INSERT INTO ' .
616 $bulk->sql_maker->_quote($source->name) . ' (' .
617 # colname list is ignored for BCP, but does no harm
618 (join ', ', map $bulk->sql_maker->_quote($_), @source_columns) . ') '.
619 ' VALUES ('. (join ', ', ('?') x @source_columns) . ')';
621 ## XXX there's a bug in the DBD::Sybase bulk support that makes $sth->finish for
622 ## a prepare_cached statement ineffective. Replace with ->sth when fixed, or
623 ## better yet the version above. Should be fixed in DBD::Sybase .
624 my $sth = $bulk->_get_dbh->prepare($sql,
628 identity_flag => $is_identity_insert,
629 identity_column => $identity_idx,
636 map [ $_, $idx++ ], @source_columns;
639 $self->_execute_array(
640 $source, $sth, \@bind, \@source_columns, \@new_data, sub {
645 $bulk->_query_end($sql);
650 DBD::Sybase::set_cslib_cb($orig_cslib_cb);
652 if ($exception =~ /-Y option/) {
655 Sybase bulk API operation failed due to character set incompatibility, reverting
656 to regular array inserts:
658 *** Try unsetting the LANG environment variable.
662 $self->_bulk_storage(undef);
667 # rollback makes the bulkLogin connection unusable
668 $self->_bulk_storage->disconnect;
669 $self->throw_exception($exception);
673 sub _dbh_execute_array {
674 my ($self, $sth, $tuple_status, $cb) = @_;
676 my $rv = $self->next::method($sth, $tuple_status);
682 # Make sure blobs are not bound as placeholders, and return any non-empty ones
684 sub _remove_blob_cols {
685 my ($self, $source, $fields) = @_;
689 for my $col (keys %$fields) {
690 if ($self->_is_lob_column($source, $col)) {
691 my $blob_val = delete $fields->{$col};
692 if (not defined $blob_val) {
693 $fields->{$col} = \'NULL';
696 $fields->{$col} = \"''";
697 $blob_cols{$col} = $blob_val unless $blob_val eq '';
702 return %blob_cols ? \%blob_cols : undef;
705 # same for insert_bulk
706 sub _remove_blob_cols_array {
707 my ($self, $source, $cols, $data) = @_;
711 for my $i (0..$#$cols) {
712 my $col = $cols->[$i];
714 if ($self->_is_lob_column($source, $col)) {
715 for my $j (0..$#$data) {
716 my $blob_val = delete $data->[$j][$i];
717 if (not defined $blob_val) {
718 $data->[$j][$i] = \'NULL';
721 $data->[$j][$i] = \"''";
722 $blob_cols[$j][$i] = $blob_val
723 unless $blob_val eq '';
729 return @blob_cols ? \@blob_cols : undef;
733 my ($self, $source, $blob_cols, $where) = @_;
735 my @primary_cols = try
736 { $source->_pri_cols }
738 $self->throw_exception("Cannot update TEXT/IMAGE column(s): $_")
741 # check if we're updating a single row by PK
742 my $pk_cols_in_where = 0;
743 for my $col (@primary_cols) {
744 $pk_cols_in_where++ if defined $where->{$col};
748 if ($pk_cols_in_where == @primary_cols) {
750 @row_to_update{@primary_cols} = @{$where}{@primary_cols};
751 @rows = \%row_to_update;
753 my $cursor = $self->select ($source, \@primary_cols, $where, {});
755 my %row; @row{@primary_cols} = @$_; \%row
759 for my $row (@rows) {
760 $self->_insert_blobs($source, $blob_cols, $row);
765 my ($self, $source, $blob_cols, $row) = @_;
766 my $dbh = $self->_get_dbh;
768 my $table = $source->name;
771 my @primary_cols = try
772 { $source->_pri_cols }
774 $self->throw_exception("Cannot update TEXT/IMAGE column(s): $_")
777 $self->throw_exception('Cannot update TEXT/IMAGE column(s) without primary key values')
778 if ((grep { defined $row{$_} } @primary_cols) != @primary_cols);
780 for my $col (keys %$blob_cols) {
781 my $blob = $blob_cols->{$col};
783 my %where = map { ($_, $row{$_}) } @primary_cols;
785 my $cursor = $self->select ($source, [$col], \%where, {});
787 my $sth = $cursor->sth;
790 $self->throw_exception(
791 "Could not find row in table '$table' for blob update:\n"
792 . Data::Dumper::Concise::Dumper (\%where)
798 $sth->func('CS_GET', 1, 'ct_data_info') or die $sth->errstr;
801 $sth->func('ct_prepare_send') or die $sth->errstr;
803 my $log_on_update = $self->_blob_log_on_update;
804 $log_on_update = 1 if not defined $log_on_update;
806 $sth->func('CS_SET', 1, {
807 total_txtlen => length($blob),
808 log_on_update => $log_on_update
809 }, 'ct_data_info') or die $sth->errstr;
811 $sth->func($blob, length($blob), 'ct_send_data') or die $sth->errstr;
813 $sth->func('ct_finish_send') or die $sth->errstr;
816 if ($self->using_freetds) {
817 $self->throw_exception (
818 "TEXT/IMAGE operation failed, probably because you are using FreeTDS: $_"
822 $self->throw_exception($_);
826 $sth->finish if $sth;
831 sub _insert_blobs_array {
832 my ($self, $source, $blob_cols, $cols, $data) = @_;
834 for my $i (0..$#$data) {
835 my $datum = $data->[$i];
838 @row{ @$cols } = @$datum;
841 for my $j (0..$#$cols) {
842 if (exists $blob_cols->[$i][$j]) {
843 $blob_vals{ $cols->[$j] } = $blob_cols->[$i][$j];
847 $self->_insert_blobs ($source, \%blob_vals, \%row);
851 =head2 connect_call_datetime_setup
855 on_connect_call => 'datetime_setup'
857 In L<connect_info|DBIx::Class::Storage::DBI/connect_info> to set:
859 $dbh->syb_date_fmt('ISO_strict'); # output fmt: 2004-08-21T14:36:48.080Z
860 $dbh->do('set dateformat mdy'); # input fmt: 08/13/1979 18:08:55.080
862 On connection for use with L<DBIx::Class::InflateColumn::DateTime>, using
863 L<DateTime::Format::Sybase>, which you will need to install.
865 This works for both C<DATETIME> and C<SMALLDATETIME> columns, although
866 C<SMALLDATETIME> columns only have minute precision.
871 my $old_dbd_warned = 0;
873 sub connect_call_datetime_setup {
875 my $dbh = $self->_get_dbh;
877 if ($dbh->can('syb_date_fmt')) {
878 # amazingly, this works with FreeTDS
879 $dbh->syb_date_fmt('ISO_strict');
880 } elsif (not $old_dbd_warned) {
881 carp "Your DBD::Sybase is too old to support ".
882 "DBIx::Class::InflateColumn::DateTime, please upgrade!";
886 $dbh->do('SET DATEFORMAT mdy');
892 sub datetime_parser_type { "DateTime::Format::Sybase" }
894 # ->begin_work and such have no effect with FreeTDS but we run them anyway to
895 # let the DBD keep any state it needs to.
897 # If they ever do start working, the extra statements will do no harm (because
898 # Sybase supports nested transactions.)
900 sub _dbh_begin_work {
903 # bulkLogin=1 connections are always in a transaction, and can only call BEGIN
904 # TRAN once. However, we need to make sure there's a $dbh.
905 return if $self->_is_bulk_storage && $self->_dbh && $self->_began_bulk_work;
907 $self->next::method(@_);
909 if ($self->using_freetds) {
910 $self->_get_dbh->do('BEGIN TRAN');
913 $self->_began_bulk_work(1) if $self->_is_bulk_storage;
918 if ($self->using_freetds) {
919 $self->_dbh->do('COMMIT');
921 return $self->next::method(@_);
926 if ($self->using_freetds) {
927 $self->_dbh->do('ROLLBACK');
929 return $self->next::method(@_);
932 # savepoint support using ASE syntax
935 my ($self, $name) = @_;
937 $self->_get_dbh->do("SAVE TRANSACTION $name");
940 # A new SAVE TRANSACTION with the same name releases the previous one.
941 sub _svp_release { 1 }
944 my ($self, $name) = @_;
946 $self->_get_dbh->do("ROLLBACK TRANSACTION $name");
951 =head1 Schema::Loader Support
953 As of version C<0.05000>, L<DBIx::Class::Schema::Loader> should work well with
954 most (if not all) versions of Sybase ASE.
958 This driver supports L<DBD::Sybase> compiled against FreeTDS
959 (L<http://www.freetds.org/>) to the best of our ability, however it is
960 recommended that you recompile L<DBD::Sybase> against the Sybase Open Client
961 libraries. They are a part of the Sybase ASE distribution:
963 The Open Client FAQ is here:
964 L<http://www.isug.com/Sybase_FAQ/ASE/section7.html>.
966 Sybase ASE for Linux (which comes with the Open Client libraries) may be
967 downloaded here: L<http://response.sybase.com/forms/ASE_Linux_Download>.
969 To see if you're using FreeTDS check C<< $schema->storage->using_freetds >>, or run:
971 perl -MDBI -le 'my $dbh = DBI->connect($dsn, $user, $pass); print $dbh->{syb_oc_version}'
973 Some versions of the libraries involved will not support placeholders, in which
974 case the storage will be reblessed to
975 L<DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars>.
977 In some configurations, placeholders will work but will throw implicit type
978 conversion errors for anything that's not expecting a string. In such a case,
979 the C<auto_cast> option from L<DBIx::Class::Storage::DBI::AutoCast> is
980 automatically set, which you may enable on connection with
981 L<DBIx::Class::Storage::DBI::AutoCast/connect_call_set_auto_cast>. The type info
982 for the C<CAST>s is taken from the L<DBIx::Class::ResultSource/data_type>
983 definitions in your Result classes, and are mapped to a Sybase type (if it isn't
984 already) using a mapping based on L<SQL::Translator>.
986 In other configurations, placeholders will work just as they do with the Sybase
987 Open Client libraries.
989 Inserts or updates of TEXT/IMAGE columns will B<NOT> work with FreeTDS.
991 =head1 INSERTS WITH PLACEHOLDERS
993 With placeholders enabled, inserts are done in a transaction so that there are
994 no concurrency issues with getting the inserted identity value using
995 C<SELECT MAX(col)>, which is the only way to get the C<IDENTITY> value in this
998 In addition, they are done on a separate connection so that it's possible to
999 have active cursors when doing an insert.
1001 When using C<DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars> transactions
1002 are disabled, as there are no concurrency issues with C<SELECT @@IDENTITY> as
1003 it's a session variable.
1007 Due to limitations of the TDS protocol, L<DBD::Sybase>, or both, you cannot
1008 begin a transaction while there are active cursors, nor can you use multiple
1009 active cursors within a transaction. An active cursor is, for example, a
1010 L<ResultSet|DBIx::Class::ResultSet> that has been executed using C<next> or
1011 C<first> but has not been exhausted or L<reset|DBIx::Class::ResultSet/reset>.
1013 For example, this will not work:
1015 $schema->txn_do(sub {
1016 my $rs = $schema->resultset('Book');
1017 while (my $row = $rs->next) {
1018 $schema->resultset('MetaData')->create({
1019 book_id => $row->id,
1027 my $first_row = $large_rs->first;
1028 $schema->txn_do(sub { ... });
1030 Transactions done for inserts in C<AutoCommit> mode when placeholders are in use
1031 are not affected, as they are done on an extra database handle.
1037 =item * use L<DBIx::Class::Storage::DBI::Replicated>
1039 =item * L<connect|DBIx::Class::Schema/connect> another L<Schema|DBIx::Class::Schema>
1041 =item * load the data from your cursor with L<DBIx::Class::ResultSet/all>
1045 =head1 MAXIMUM CONNECTIONS
1047 The TDS protocol makes separate connections to the server for active statements
1048 in the background. By default the number of such connections is limited to 25,
1049 on both the client side and the server side.
1051 This is a bit too low for a complex L<DBIx::Class> application, so on connection
1052 the client side setting is set to C<256> (see L<DBD::Sybase/maxConnect>.) You
1053 can override it to whatever setting you like in the DSN.
1056 L<http://infocenter.sybase.com/help/index.jsp?topic=/com.sybase.help.ase_15.0.sag1/html/sag1/sag1272.htm>
1057 for information on changing the setting on the server side.
1061 See L</connect_call_datetime_setup> to setup date formats
1062 for L<DBIx::Class::InflateColumn::DateTime>.
1064 =head1 TEXT/IMAGE COLUMNS
1066 L<DBD::Sybase> compiled with FreeTDS will B<NOT> allow you to insert or update
1067 C<TEXT/IMAGE> columns.
1069 Setting C<< $dbh->{LongReadLen} >> will also not work with FreeTDS use either:
1071 $schema->storage->dbh->do("SET TEXTSIZE $bytes");
1075 $schema->storage->set_textsize($bytes);
1079 However, the C<LongReadLen> you pass in
1080 L<connect_info|DBIx::Class::Storage::DBI/connect_info> is used to execute the
1081 equivalent C<SET TEXTSIZE> command on connection.
1083 See L</connect_call_blob_setup> for a
1084 L<connect_info|DBIx::Class::Storage::DBI/connect_info> setting you need to work
1085 with C<IMAGE> columns.
1089 The experimental L<DBD::Sybase> Bulk API support is used for
1090 L<populate|DBIx::Class::ResultSet/populate> in B<void> context, in a transaction
1091 on a separate connection.
1093 To use this feature effectively, use a large number of rows for each
1094 L<populate|DBIx::Class::ResultSet/populate> call, eg.:
1096 while (my $rows = $data_source->get_100_rows()) {
1097 $rs->populate($rows);
1100 B<NOTE:> the L<add_columns|DBIx::Class::ResultSource/add_columns>
1101 calls in your C<Result> classes B<must> list columns in database order for this
1102 to work. Also, you may have to unset the C<LANG> environment variable before
1103 loading your app, if it doesn't match the character set of your database.
1105 When inserting IMAGE columns using this method, you'll need to use
1106 L</connect_call_blob_setup> as well.
1108 =head1 COMPUTED COLUMNS
1110 If you have columns such as:
1112 created_dtm AS getdate()
1114 represent them in your Result classes as:
1118 default_value => \'getdate()',
1122 The C<data_type> must exist and must be C<undef>. Then empty inserts will work
1123 on tables with such columns.
1125 =head1 TIMESTAMP COLUMNS
1127 C<timestamp> columns in Sybase ASE are not really timestamps, see:
1128 L<http://dba.fyicenter.com/Interview-Questions/SYBASE/The_timestamp_datatype_in_Sybase_.html>.
1130 They should be defined in your Result classes as:
1133 data_type => 'timestamp',
1135 inflate_datetime => 0,
1138 The C<<inflate_datetime => 0>> is necessary if you use
1139 L<DBIx::Class::InflateColumn::DateTime>, and most people do, and still want to
1140 be able to read these values.
1142 The values will come back as hexadecimal.
1150 Transitions to AutoCommit=0 (starting a transaction) mode by exhausting
1151 any active cursors, using eager cursors.
1155 Real limits and limited counts using stored procedures deployed on startup.
1159 Adaptive Server Anywhere (ASA) support, with possible SQLA::Limit support.
1163 Blob update with a LIKE query on a blob, without invalidating the WHERE condition.
1167 bulk_insert using prepare_cached (see comments.)
1173 See L<DBIx::Class/CONTRIBUTORS>.
1177 You may distribute this code under the same terms as Perl itself.