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();
17 __PACKAGE__->mk_group_accessors('simple' =>
18 qw/_identity _blob_log_on_update _writer_storage _is_extra_storage
19 _bulk_storage _is_bulk_storage _began_bulk_work
20 _bulk_disabled_due_to_coderef_connect_info_warned
24 my @also_proxy_to_extra_storages = qw/
25 connect_call_set_auto_cast auto_cast connect_call_blob_setup
26 connect_call_datetime_setup
28 disconnect _connect_info _sql_maker _sql_maker_opts disable_sth_caching
29 auto_savepoint unsafe cursor_class debug debugobj schema
34 DBIx::Class::Storage::DBI::Sybase::ASE - Sybase ASE SQL Server support for
39 This subclass supports L<DBD::Sybase> for real (non-Microsoft) Sybase databases.
43 If your version of Sybase does not support placeholders, then your storage will
44 be reblessed to L<DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars>.
45 You can also enable that driver explicitly, see the documentation for more
48 With this driver there is unfortunately no way to get the C<last_insert_id>
49 without doing a C<SELECT MAX(col)>. This is done safely in a transaction
50 (locking the table.) See L</INSERTS WITH PLACEHOLDERS>.
52 A recommended L<connect_info|DBIx::Class::Storage::DBI/connect_info> setting:
54 on_connect_call => [['datetime_setup'], ['blob_setup', log_on_update => 0]]
63 my $no_bind_vars = __PACKAGE__ . '::NoBindVars';
65 if ($self->using_freetds) {
66 carp <<'EOF' unless $ENV{DBIC_SYBASE_FREETDS_NOWARN};
68 You are using FreeTDS with Sybase.
70 We will do our best to support this configuration, but please consider this
73 TEXT/IMAGE columns will definitely not work.
75 You are encouraged to recompile DBD::Sybase with the Sybase Open Client libraries
78 See perldoc DBIx::Class::Storage::DBI::Sybase::ASE for more details.
80 To turn off this warning set the DBIC_SYBASE_FREETDS_NOWARN environment
84 if (not $self->_typeless_placeholders_supported) {
85 if ($self->_placeholders_supported) {
89 $self->ensure_class_loaded($no_bind_vars);
90 bless $self, $no_bind_vars;
96 elsif (not $self->_get_dbh->{syb_dynamic_supported}) {
97 # not necessarily FreeTDS, but no placeholders nevertheless
98 $self->ensure_class_loaded($no_bind_vars);
99 bless $self, $no_bind_vars;
102 # this is highly unlikely, but we check just in case
103 elsif (not $self->_typeless_placeholders_supported) {
110 $self->_set_max_connect(256);
112 # create storage for insert/(update blob) transactions,
113 # unless this is that storage
114 return if $self->_is_extra_storage;
116 my $writer_storage = (ref $self)->new;
118 $writer_storage->_is_extra_storage(1);
119 $writer_storage->connect_info($self->connect_info);
120 $writer_storage->auto_cast($self->auto_cast);
122 $self->_writer_storage($writer_storage);
124 # create a bulk storage unless connect_info is a coderef
125 return if ref($self->_dbi_connect_info->[0]) eq 'CODE';
127 my $bulk_storage = (ref $self)->new;
129 $bulk_storage->_is_extra_storage(1);
130 $bulk_storage->_is_bulk_storage(1); # for special ->disconnect acrobatics
131 $bulk_storage->connect_info($self->connect_info);
134 $bulk_storage->_dbi_connect_info->[0] .= ';bulkLogin=1';
136 $self->_bulk_storage($bulk_storage);
139 for my $method (@also_proxy_to_extra_storages) {
141 no warnings 'redefine';
143 my $replaced = __PACKAGE__->can($method);
145 *{$method} = Sub::Name::subname $method => sub {
147 $self->_writer_storage->$replaced(@_) if $self->_writer_storage;
148 $self->_bulk_storage->$replaced(@_) if $self->_bulk_storage;
149 return $self->$replaced(@_);
156 # Even though we call $sth->finish for uses off the bulk API, there's still an
157 # "active statement" warning on disconnect, which we throw away here.
158 # This is due to the bug described in insert_bulk.
159 # Currently a noop because 'prepare' is used instead of 'prepare_cached'.
160 local $SIG{__WARN__} = sub {
161 warn $_[0] unless $_[0] =~ /active statement/i;
162 } if $self->_is_bulk_storage;
164 # so that next transaction gets a dbh
165 $self->_began_bulk_work(0) if $self->_is_bulk_storage;
170 # Set up session settings for Sybase databases for the connection.
172 # Make sure we have CHAINED mode turned on if AutoCommit is off in non-FreeTDS
173 # DBD::Sybase (since we don't know how DBD::Sybase was compiled.) If however
174 # we're using FreeTDS, CHAINED mode turns on an implicit transaction which we
175 # only want when AutoCommit is off.
177 # Also SET TEXTSIZE for FreeTDS because LongReadLen doesn't work.
178 sub _run_connection_actions {
181 if ($self->_is_bulk_storage) {
182 # this should be cleared on every reconnect
183 $self->_began_bulk_work(0);
187 if (not $self->using_freetds) {
188 $self->_dbh->{syb_chained_txn} = 1;
190 # based on LongReadLen in connect_info
193 if ($self->_dbh_autocommit) {
194 $self->_dbh->do('SET CHAINED OFF');
196 $self->_dbh->do('SET CHAINED ON');
200 $self->next::method(@_);
203 =head2 connect_call_blob_setup
207 on_connect_call => [ [ 'blob_setup', log_on_update => 0 ] ]
209 Does C<< $dbh->{syb_binary_images} = 1; >> to return C<IMAGE> data as raw binary
210 instead of as a hex string.
214 Also sets the C<log_on_update> value for blob write operations. The default is
215 C<1>, but C<0> is better if your database is configured for it.
218 L<DBD::Sybase/Handling_IMAGE/TEXT_data_with_syb_ct_get_data()/syb_ct_send_data()>.
222 sub connect_call_blob_setup {
225 my $dbh = $self->_dbh;
226 $dbh->{syb_binary_images} = 1;
228 $self->_blob_log_on_update($args{log_on_update})
229 if exists $args{log_on_update};
235 $type && $type =~ /(?:text|image|lob|bytea|binary|memo)/i;
239 my ($self, $source, $column) = @_;
241 return $self->_is_lob_type($source->column_info($column)->{data_type});
244 sub _prep_for_execute {
246 my ($op, $extra_bind, $ident, $args) = @_;
248 my ($sql, $bind) = $self->next::method (@_);
250 my $table = Scalar::Util::blessed($ident) ? $ident->from : $ident;
252 my $bind_info = $self->_resolve_column_info(
253 $ident, [map $_->[0], @{$bind}]
255 my $bound_identity_col = List::Util::first
256 { $bind_info->{$_}{is_auto_increment} }
259 my $identity_col = Scalar::Util::blessed($ident) &&
261 { $ident->column_info($_)->{is_auto_increment} }
265 if (($op eq 'insert' && $bound_identity_col) ||
266 ($op eq 'update' && exists $args->[0]{$identity_col})) {
268 $self->_set_table_identity_sql($op => $table, 'on'),
270 $self->_set_table_identity_sql($op => $table, 'off'),
274 if ($op eq 'insert' && (not $bound_identity_col) && $identity_col &&
275 (not $self->{insert_bulk})) {
278 $self->_fetch_identity_sql($ident, $identity_col);
281 return ($sql, $bind);
284 sub _set_table_identity_sql {
285 my ($self, $op, $table, $on_off) = @_;
287 return sprintf 'SET IDENTITY_%s %s %s',
288 uc($op), $self->sql_maker->_quote($table), uc($on_off);
291 # Stolen from SQLT, with some modifications. This is a makeshift
292 # solution before a sane type-mapping library is available, thus
293 # the 'our' for easy overrides.
294 our %TYPE_MAPPING = (
297 varchar => 'varchar',
298 varchar2 => 'varchar',
299 timestamp => 'datetime',
301 real => 'double precision',
304 tinyint => 'smallint',
305 float => 'double precision',
307 bigserial => 'numeric',
308 boolean => 'varchar',
312 sub _native_data_type {
313 my ($self, $type) = @_;
316 $type =~ s/\s* identity//x;
318 return uc($TYPE_MAPPING{$type} || $type);
321 sub _fetch_identity_sql {
322 my ($self, $source, $col) = @_;
324 return sprintf ("SELECT MAX(%s) FROM %s",
325 map { $self->sql_maker->_quote ($_) } ($col, $source->from)
333 my ($rv, $sth, @bind) = $self->dbh_do($self->can('_dbh_execute'), @_);
335 if ($op eq 'insert') {
336 $self->_identity($sth->fetchrow_array);
340 return wantarray ? ($rv, $sth, @bind) : $rv;
343 sub last_insert_id { shift->_identity }
345 # handles TEXT/IMAGE and transaction for last_insert_id
348 my ($source, $to_insert) = @_;
350 my $identity_col = (List::Util::first
351 { $source->column_info($_)->{is_auto_increment} }
352 $source->columns) || '';
354 # check for empty insert
355 # INSERT INTO foo DEFAULT VALUES -- does not work with Sybase
356 # try to insert explicit 'DEFAULT's instead (except for identity, timestamp
357 # and computed columns)
358 if (not %$to_insert) {
359 for my $col ($source->columns) {
360 next if $col eq $identity_col;
362 my $info = $source->column_info($col);
364 next if ref $info->{default_value} eq 'SCALAR'
365 || (exists $info->{data_type} && (not defined $info->{data_type}));
367 next if $info->{data_type} && $info->{data_type} =~ /^timestamp\z/i;
369 $to_insert->{$col} = \'DEFAULT';
373 my $blob_cols = $self->_remove_blob_cols($source, $to_insert);
375 # do we need the horrific SELECT MAX(COL) hack?
376 my $dumb_last_insert_id =
378 && (not exists $to_insert->{$identity_col})
379 && ($self->_identity_method||'') ne '@@IDENTITY';
381 my $next = $self->next::can;
383 # we are already in a transaction, or there are no blobs
384 # and we don't need the PK - just (try to) do it
385 if ($self->{transaction_depth}
386 || (!$blob_cols && !$dumb_last_insert_id)
388 return $self->_insert (
389 $next, $source, $to_insert, $blob_cols, $identity_col
393 # otherwise use the _writer_storage to do the insert+transaction on another
395 my $guard = $self->_writer_storage->txn_scope_guard;
397 my $updated_cols = $self->_writer_storage->_insert (
398 $next, $source, $to_insert, $blob_cols, $identity_col
401 $self->_identity($self->_writer_storage->_identity);
405 return $updated_cols;
409 my ($self, $next, $source, $to_insert, $blob_cols, $identity_col) = @_;
411 my $updated_cols = $self->$next ($source, $to_insert);
415 ($identity_col => $self->last_insert_id($source, $identity_col)) : ()),
420 $self->_insert_blobs ($source, $blob_cols, $final_row) if $blob_cols;
422 return $updated_cols;
427 my ($source, $fields, $where, @rest) = @_;
429 my $wantarray = wantarray;
431 my $blob_cols = $self->_remove_blob_cols($source, $fields);
433 my $table = $source->name;
435 my $identity_col = List::Util::first
436 { $source->column_info($_)->{is_auto_increment} }
439 my $is_identity_update = $identity_col && defined $fields->{$identity_col};
441 return $self->next::method(@_) unless $blob_cols;
443 # If there are any blobs in $where, Sybase will return a descriptive error
445 # XXX blobs can still be used with a LIKE query, and this should be handled.
447 # update+blob update(s) done atomically on separate connection
448 $self = $self->_writer_storage;
450 my $guard = $self->txn_scope_guard;
452 # First update the blob columns to be updated to '' (taken from $fields, where
453 # it is originally put by _remove_blob_cols .)
454 my %blobs_to_empty = map { ($_ => delete $fields->{$_}) } keys %$blob_cols;
456 # We can't only update NULL blobs, because blobs cannot be in the WHERE clause.
458 $self->next::method($source, \%blobs_to_empty, $where, @rest);
460 # Now update the blobs before the other columns in case the update of other
461 # columns makes the search condition invalid.
462 $self->_update_blobs($source, $blob_cols, $where);
467 @res = $self->next::method(@_);
469 elsif (defined $wantarray) {
470 $res[0] = $self->next::method(@_);
473 $self->next::method(@_);
479 return $wantarray ? @res : $res[0];
484 my ($source, $cols, $data) = @_;
486 my $identity_col = List::Util::first
487 { $source->column_info($_)->{is_auto_increment} }
490 my $is_identity_insert = (List::Util::first
491 { $_ eq $identity_col }
495 my @source_columns = $source->columns;
498 $self->_bulk_storage &&
499 $self->_get_dbh->{syb_has_blk};
501 if ((not $use_bulk_api)
503 (ref($self->_dbi_connect_info->[0]) eq 'CODE')
505 (not $self->_bulk_disabled_due_to_coderef_connect_info_warned)) {
507 Bulk API support disabled due to use of a CODEREF connect_info. Reverting to
508 regular array inserts.
510 $self->_bulk_disabled_due_to_coderef_connect_info_warned(1);
513 if (not $use_bulk_api) {
514 my $blob_cols = $self->_remove_blob_cols_array($source, $cols, $data);
516 # _execute_array uses a txn anyway, but it ends too early in case we need to
517 # select max(col) to get the identity for inserting blobs.
518 ($self, my $guard) = $self->{transaction_depth} == 0 ?
519 ($self->_writer_storage, $self->_writer_storage->txn_scope_guard)
523 local $self->{insert_bulk} = 1;
525 $self->next::method(@_);
528 if ($is_identity_insert) {
529 $self->_insert_blobs_array ($source, $blob_cols, $cols, $data);
532 my @cols_with_identities = (@$cols, $identity_col);
534 ## calculate identities
535 # XXX This assumes identities always increase by 1, which may or may not
537 my ($last_identity) =
538 $self->_dbh->selectrow_array (
539 $self->_fetch_identity_sql($source, $identity_col)
541 my @identities = (($last_identity - @$data + 1) .. $last_identity);
543 my @data_with_identities = map [@$_, shift @identities], @$data;
545 $self->_insert_blobs_array (
546 $source, $blob_cols, \@cols_with_identities, \@data_with_identities
551 $guard->commit if $guard;
556 # otherwise, use the bulk API
558 # rearrange @$data so that columns are in database order
560 @orig_idx{@$cols} = 0..$#$cols;
563 @new_idx{@source_columns} = 0..$#source_columns;
566 for my $datum (@$data) {
568 for my $col (@source_columns) {
569 # identity data will be 'undef' if not $is_identity_insert
570 # columns with defaults will also be 'undef'
571 $new_datum->[ $new_idx{$col} ] =
572 exists $orig_idx{$col} ? $datum->[ $orig_idx{$col} ] : undef;
574 push @new_data, $new_datum;
577 # bcp identity index is 1-based
578 my $identity_idx = exists $new_idx{$identity_col} ?
579 $new_idx{$identity_col} + 1 : 0;
581 ## Set a client-side conversion error handler, straight from DBD::Sybase docs.
582 # This ignores any data conversion errors detected by the client side libs, as
583 # they are usually harmless.
584 my $orig_cslib_cb = DBD::Sybase::set_cslib_cb(
585 Sub::Name::subname insert_bulk => sub {
586 my ($layer, $origin, $severity, $errno, $errmsg, $osmsg, $blkmsg) = @_;
588 return 1 if $errno == 36;
591 "Layer: $layer, Origin: $origin, Severity: $severity, Error: $errno" .
592 ($errmsg ? "\n$errmsg" : '') .
593 ($osmsg ? "\n$osmsg" : '') .
594 ($blkmsg ? "\n$blkmsg" : '');
600 my $bulk = $self->_bulk_storage;
602 my $guard = $bulk->txn_scope_guard;
604 ## XXX get this to work instead of our own $sth
605 ## will require SQLA or *Hacks changes for ordered columns
606 # $bulk->next::method($source, \@source_columns, \@new_data, {
607 # syb_bcp_attribs => {
608 # identity_flag => $is_identity_insert,
609 # identity_column => $identity_idx,
612 my $sql = 'INSERT INTO ' .
613 $bulk->sql_maker->_quote($source->name) . ' (' .
614 # colname list is ignored for BCP, but does no harm
615 (join ', ', map $bulk->sql_maker->_quote($_), @source_columns) . ') '.
616 ' VALUES ('. (join ', ', ('?') x @source_columns) . ')';
618 ## XXX there's a bug in the DBD::Sybase bulk support that makes $sth->finish for
619 ## a prepare_cached statement ineffective. Replace with ->sth when fixed, or
620 ## better yet the version above. Should be fixed in DBD::Sybase .
621 my $sth = $bulk->_get_dbh->prepare($sql,
625 identity_flag => $is_identity_insert,
626 identity_column => $identity_idx,
633 map [ $_, $idx++ ], @source_columns;
636 $self->_execute_array(
637 $source, $sth, \@bind, \@source_columns, \@new_data, sub {
642 $bulk->_query_end($sql);
646 DBD::Sybase::set_cslib_cb($orig_cslib_cb);
648 if ($exception =~ /-Y option/) {
651 Sybase bulk API operation failed due to character set incompatibility, reverting
652 to regular array inserts:
654 *** Try unsetting the LANG environment variable.
658 $self->_bulk_storage(undef);
663 # rollback makes the bulkLogin connection unusable
664 $self->_bulk_storage->disconnect;
665 $self->throw_exception($exception);
669 sub _dbh_execute_array {
670 my ($self, $sth, $tuple_status, $cb) = @_;
672 my $rv = $self->next::method($sth, $tuple_status);
678 # Make sure blobs are not bound as placeholders, and return any non-empty ones
680 sub _remove_blob_cols {
681 my ($self, $source, $fields) = @_;
685 for my $col (keys %$fields) {
686 if ($self->_is_lob_column($source, $col)) {
687 my $blob_val = delete $fields->{$col};
688 if (not defined $blob_val) {
689 $fields->{$col} = \'NULL';
692 $fields->{$col} = \"''";
693 $blob_cols{$col} = $blob_val unless $blob_val eq '';
698 return %blob_cols ? \%blob_cols : undef;
701 # same for insert_bulk
702 sub _remove_blob_cols_array {
703 my ($self, $source, $cols, $data) = @_;
707 for my $i (0..$#$cols) {
708 my $col = $cols->[$i];
710 if ($self->_is_lob_column($source, $col)) {
711 for my $j (0..$#$data) {
712 my $blob_val = delete $data->[$j][$i];
713 if (not defined $blob_val) {
714 $data->[$j][$i] = \'NULL';
717 $data->[$j][$i] = \"''";
718 $blob_cols[$j][$i] = $blob_val
719 unless $blob_val eq '';
725 return @blob_cols ? \@blob_cols : undef;
729 my ($self, $source, $blob_cols, $where) = @_;
731 my @primary_cols = eval { $source->_pri_cols };
732 $self->throw_exception("Cannot update TEXT/IMAGE column(s): $@")
735 # check if we're updating a single row by PK
736 my $pk_cols_in_where = 0;
737 for my $col (@primary_cols) {
738 $pk_cols_in_where++ if defined $where->{$col};
742 if ($pk_cols_in_where == @primary_cols) {
744 @row_to_update{@primary_cols} = @{$where}{@primary_cols};
745 @rows = \%row_to_update;
747 my $cursor = $self->select ($source, \@primary_cols, $where, {});
749 my %row; @row{@primary_cols} = @$_; \%row
753 for my $row (@rows) {
754 $self->_insert_blobs($source, $blob_cols, $row);
759 my ($self, $source, $blob_cols, $row) = @_;
760 my $dbh = $self->_get_dbh;
762 my $table = $source->name;
765 my @primary_cols = eval { $source->_pri_cols} ;
766 $self->throw_exception("Cannot update TEXT/IMAGE column(s): $@")
769 $self->throw_exception('Cannot update TEXT/IMAGE column(s) without primary key values')
770 if ((grep { defined $row{$_} } @primary_cols) != @primary_cols);
772 for my $col (keys %$blob_cols) {
773 my $blob = $blob_cols->{$col};
775 my %where = map { ($_, $row{$_}) } @primary_cols;
777 my $cursor = $self->select ($source, [$col], \%where, {});
779 my $sth = $cursor->sth;
783 $self->throw_exception(
784 "Could not find row in table '$table' for blob update:\n"
785 . Data::Dumper::Concise::Dumper (\%where)
791 $sth->func('CS_GET', 1, 'ct_data_info') or die $sth->errstr;
794 $sth->func('ct_prepare_send') or die $sth->errstr;
796 my $log_on_update = $self->_blob_log_on_update;
797 $log_on_update = 1 if not defined $log_on_update;
799 $sth->func('CS_SET', 1, {
800 total_txtlen => length($blob),
801 log_on_update => $log_on_update
802 }, 'ct_data_info') or die $sth->errstr;
804 $sth->func($blob, length($blob), 'ct_send_data') or die $sth->errstr;
806 $sth->func('ct_finish_send') or die $sth->errstr;
809 $sth->finish if $sth;
811 if ($self->using_freetds) {
812 $self->throw_exception (
813 'TEXT/IMAGE operation failed, probably because you are using FreeTDS: '
817 $self->throw_exception($exception);
823 sub _insert_blobs_array {
824 my ($self, $source, $blob_cols, $cols, $data) = @_;
826 for my $i (0..$#$data) {
827 my $datum = $data->[$i];
830 @row{ @$cols } = @$datum;
833 for my $j (0..$#$cols) {
834 if (exists $blob_cols->[$i][$j]) {
835 $blob_vals{ $cols->[$j] } = $blob_cols->[$i][$j];
839 $self->_insert_blobs ($source, \%blob_vals, \%row);
843 =head2 connect_call_datetime_setup
847 on_connect_call => 'datetime_setup'
849 In L<connect_info|DBIx::Class::Storage::DBI/connect_info> to set:
851 $dbh->syb_date_fmt('ISO_strict'); # output fmt: 2004-08-21T14:36:48.080Z
852 $dbh->do('set dateformat mdy'); # input fmt: 08/13/1979 18:08:55.080
854 On connection for use with L<DBIx::Class::InflateColumn::DateTime>, using
855 L<DateTime::Format::Sybase>, which you will need to install.
857 This works for both C<DATETIME> and C<SMALLDATETIME> columns, although
858 C<SMALLDATETIME> columns only have minute precision.
863 my $old_dbd_warned = 0;
865 sub connect_call_datetime_setup {
867 my $dbh = $self->_get_dbh;
869 if ($dbh->can('syb_date_fmt')) {
870 # amazingly, this works with FreeTDS
871 $dbh->syb_date_fmt('ISO_strict');
872 } elsif (not $old_dbd_warned) {
873 carp "Your DBD::Sybase is too old to support ".
874 "DBIx::Class::InflateColumn::DateTime, please upgrade!";
878 $dbh->do('SET DATEFORMAT mdy');
884 sub datetime_parser_type { "DateTime::Format::Sybase" }
886 # ->begin_work and such have no effect with FreeTDS but we run them anyway to
887 # let the DBD keep any state it needs to.
889 # If they ever do start working, the extra statements will do no harm (because
890 # Sybase supports nested transactions.)
892 sub _dbh_begin_work {
895 # bulkLogin=1 connections are always in a transaction, and can only call BEGIN
896 # TRAN once. However, we need to make sure there's a $dbh.
897 return if $self->_is_bulk_storage && $self->_dbh && $self->_began_bulk_work;
899 $self->next::method(@_);
901 if ($self->using_freetds) {
902 $self->_get_dbh->do('BEGIN TRAN');
905 $self->_began_bulk_work(1) if $self->_is_bulk_storage;
910 if ($self->using_freetds) {
911 $self->_dbh->do('COMMIT');
913 return $self->next::method(@_);
918 if ($self->using_freetds) {
919 $self->_dbh->do('ROLLBACK');
921 return $self->next::method(@_);
924 # savepoint support using ASE syntax
927 my ($self, $name) = @_;
929 $self->_get_dbh->do("SAVE TRANSACTION $name");
932 # A new SAVE TRANSACTION with the same name releases the previous one.
933 sub _svp_release { 1 }
936 my ($self, $name) = @_;
938 $self->_get_dbh->do("ROLLBACK TRANSACTION $name");
943 =head1 Schema::Loader Support
945 As of version C<0.05000>, L<DBIx::Class::Schema::Loader> should work well with
946 most (if not all) versions of Sybase ASE.
950 This driver supports L<DBD::Sybase> compiled against FreeTDS
951 (L<http://www.freetds.org/>) to the best of our ability, however it is
952 recommended that you recompile L<DBD::Sybase> against the Sybase Open Client
953 libraries. They are a part of the Sybase ASE distribution:
955 The Open Client FAQ is here:
956 L<http://www.isug.com/Sybase_FAQ/ASE/section7.html>.
958 Sybase ASE for Linux (which comes with the Open Client libraries) may be
959 downloaded here: L<http://response.sybase.com/forms/ASE_Linux_Download>.
961 To see if you're using FreeTDS check C<< $schema->storage->using_freetds >>, or run:
963 perl -MDBI -le 'my $dbh = DBI->connect($dsn, $user, $pass); print $dbh->{syb_oc_version}'
965 Some versions of the libraries involved will not support placeholders, in which
966 case the storage will be reblessed to
967 L<DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars>.
969 In some configurations, placeholders will work but will throw implicit type
970 conversion errors for anything that's not expecting a string. In such a case,
971 the C<auto_cast> option from L<DBIx::Class::Storage::DBI::AutoCast> is
972 automatically set, which you may enable on connection with
973 L<DBIx::Class::Storage::DBI::AutoCast/connect_call_set_auto_cast>. The type info
974 for the C<CAST>s is taken from the L<DBIx::Class::ResultSource/data_type>
975 definitions in your Result classes, and are mapped to a Sybase type (if it isn't
976 already) using a mapping based on L<SQL::Translator>.
978 In other configurations, placeholders will work just as they do with the Sybase
979 Open Client libraries.
981 Inserts or updates of TEXT/IMAGE columns will B<NOT> work with FreeTDS.
983 =head1 INSERTS WITH PLACEHOLDERS
985 With placeholders enabled, inserts are done in a transaction so that there are
986 no concurrency issues with getting the inserted identity value using
987 C<SELECT MAX(col)>, which is the only way to get the C<IDENTITY> value in this
990 In addition, they are done on a separate connection so that it's possible to
991 have active cursors when doing an insert.
993 When using C<DBIx::Class::Storage::DBI::Sybase::ASE::NoBindVars> transactions
994 are disabled, as there are no concurrency issues with C<SELECT @@IDENTITY> as
995 it's a session variable.
999 Due to limitations of the TDS protocol, L<DBD::Sybase>, or both, you cannot
1000 begin a transaction while there are active cursors, nor can you use multiple
1001 active cursors within a transaction. An active cursor is, for example, a
1002 L<ResultSet|DBIx::Class::ResultSet> that has been executed using C<next> or
1003 C<first> but has not been exhausted or L<reset|DBIx::Class::ResultSet/reset>.
1005 For example, this will not work:
1007 $schema->txn_do(sub {
1008 my $rs = $schema->resultset('Book');
1009 while (my $row = $rs->next) {
1010 $schema->resultset('MetaData')->create({
1011 book_id => $row->id,
1019 my $first_row = $large_rs->first;
1020 $schema->txn_do(sub { ... });
1022 Transactions done for inserts in C<AutoCommit> mode when placeholders are in use
1023 are not affected, as they are done on an extra database handle.
1029 =item * use L<DBIx::Class::Storage::DBI::Replicated>
1031 =item * L<connect|DBIx::Class::Schema/connect> another L<Schema|DBIx::Class::Schema>
1033 =item * load the data from your cursor with L<DBIx::Class::ResultSet/all>
1037 =head1 MAXIMUM CONNECTIONS
1039 The TDS protocol makes separate connections to the server for active statements
1040 in the background. By default the number of such connections is limited to 25,
1041 on both the client side and the server side.
1043 This is a bit too low for a complex L<DBIx::Class> application, so on connection
1044 the client side setting is set to C<256> (see L<DBD::Sybase/maxConnect>.) You
1045 can override it to whatever setting you like in the DSN.
1048 L<http://infocenter.sybase.com/help/index.jsp?topic=/com.sybase.help.ase_15.0.sag1/html/sag1/sag1272.htm>
1049 for information on changing the setting on the server side.
1053 See L</connect_call_datetime_setup> to setup date formats
1054 for L<DBIx::Class::InflateColumn::DateTime>.
1056 =head1 TEXT/IMAGE COLUMNS
1058 L<DBD::Sybase> compiled with FreeTDS will B<NOT> allow you to insert or update
1059 C<TEXT/IMAGE> columns.
1061 Setting C<< $dbh->{LongReadLen} >> will also not work with FreeTDS use either:
1063 $schema->storage->dbh->do("SET TEXTSIZE $bytes");
1067 $schema->storage->set_textsize($bytes);
1071 However, the C<LongReadLen> you pass in
1072 L<connect_info|DBIx::Class::Storage::DBI/connect_info> is used to execute the
1073 equivalent C<SET TEXTSIZE> command on connection.
1075 See L</connect_call_blob_setup> for a
1076 L<connect_info|DBIx::Class::Storage::DBI/connect_info> setting you need to work
1077 with C<IMAGE> columns.
1081 The experimental L<DBD::Sybase> Bulk API support is used for
1082 L<populate|DBIx::Class::ResultSet/populate> in B<void> context, in a transaction
1083 on a separate connection.
1085 To use this feature effectively, use a large number of rows for each
1086 L<populate|DBIx::Class::ResultSet/populate> call, eg.:
1088 while (my $rows = $data_source->get_100_rows()) {
1089 $rs->populate($rows);
1092 B<NOTE:> the L<add_columns|DBIx::Class::ResultSource/add_columns>
1093 calls in your C<Result> classes B<must> list columns in database order for this
1094 to work. Also, you may have to unset the C<LANG> environment variable before
1095 loading your app, if it doesn't match the character set of your database.
1097 When inserting IMAGE columns using this method, you'll need to use
1098 L</connect_call_blob_setup> as well.
1100 =head1 COMPUTED COLUMNS
1102 If you have columns such as:
1104 created_dtm AS getdate()
1106 represent them in your Result classes as:
1110 default_value => \'getdate()',
1114 The C<data_type> must exist and must be C<undef>. Then empty inserts will work
1115 on tables with such columns.
1117 =head1 TIMESTAMP COLUMNS
1119 C<timestamp> columns in Sybase ASE are not really timestamps, see:
1120 L<http://dba.fyicenter.com/Interview-Questions/SYBASE/The_timestamp_datatype_in_Sybase_.html>.
1122 They should be defined in your Result classes as:
1125 data_type => 'timestamp',
1127 inflate_datetime => 0,
1130 The C<<inflate_datetime => 0>> is necessary if you use
1131 L<DBIx::Class::InflateColumn::DateTime>, and most people do, and still want to
1132 be able to read these values.
1134 The values will come back as hexadecimal.
1142 Transitions to AutoCommit=0 (starting a transaction) mode by exhausting
1143 any active cursors, using eager cursors.
1147 Real limits and limited counts using stored procedures deployed on startup.
1151 Adaptive Server Anywhere (ASA) support, with possible SQLA::Limit support.
1155 Blob update with a LIKE query on a blob, without invalidating the WHERE condition.
1159 bulk_insert using prepare_cached (see comments.)
1165 See L<DBIx::Class/CONTRIBUTORS>.
1169 You may distribute this code under the same terms as Perl itself.