Commit | Line | Data |
75d07914 |
1 | package DBIx::Class::Storage::DBI::MSSQL; |
3885cff6 |
2 | |
75d07914 |
3 | use strict; |
4 | use warnings; |
3885cff6 |
5 | |
48fe9087 |
6 | use base qw/DBIx::Class::Storage::DBI::AmbiguousGlob DBIx::Class::Storage::DBI/; |
2ad62d97 |
7 | use mro 'c3'; |
3885cff6 |
8 | |
5a77aa8b |
9 | use List::Util(); |
10 | |
7b1b2582 |
11 | __PACKAGE__->mk_group_accessors(simple => qw/ |
12 | _identity _identity_method |
13 | /); |
14 | |
ac93965c |
15 | __PACKAGE__->sql_maker_class('DBIx::Class::SQLAHacks::MSSQL'); |
16 | |
afcfff01 |
17 | sub _set_identity_insert { |
18 | my ($self, $table) = @_; |
64690266 |
19 | |
20 | my $sql = sprintf ( |
afcfff01 |
21 | 'SET IDENTITY_INSERT %s ON', |
64690266 |
22 | $self->sql_maker->_quote ($table), |
afcfff01 |
23 | ); |
64690266 |
24 | |
25 | my $dbh = $self->_get_dbh; |
26 | eval { $dbh->do ($sql) }; |
27 | if ($@) { |
28 | $self->throw_exception (sprintf "Error executing '%s': %s", |
29 | $sql, |
30 | $dbh->errstr, |
31 | ); |
32 | } |
afcfff01 |
33 | } |
34 | |
aac1a358 |
35 | sub _unset_identity_insert { |
36 | my ($self, $table) = @_; |
37 | |
38 | my $sql = sprintf ( |
39 | 'SET IDENTITY_INSERT %s OFF', |
40 | $self->sql_maker->_quote ($table), |
41 | ); |
42 | |
43 | my $dbh = $self->_get_dbh; |
44 | $dbh->do ($sql); |
45 | } |
46 | |
5a77aa8b |
47 | sub insert_bulk { |
48 | my $self = shift; |
49 | my ($source, $cols, $data) = @_; |
50 | |
aac1a358 |
51 | my $is_identity_insert = (List::Util::first |
afcfff01 |
52 | { $source->column_info ($_)->{is_auto_increment} } |
53 | (@{$cols}) |
aac1a358 |
54 | ) |
55 | ? 1 |
56 | : 0; |
5a77aa8b |
57 | |
aac1a358 |
58 | if ($is_identity_insert) { |
59 | $self->_set_identity_insert ($source->name); |
5a77aa8b |
60 | } |
61 | |
62 | $self->next::method(@_); |
63 | |
aac1a358 |
64 | if ($is_identity_insert) { |
65 | $self->_unset_identity_insert ($source->name); |
5a77aa8b |
66 | } |
67 | } |
68 | |
57ee81d0 |
69 | # support MSSQL GUID column types |
70 | |
ca791b95 |
71 | sub insert { |
72 | my $self = shift; |
73 | my ($source, $to_insert) = @_; |
74 | |
afcfff01 |
75 | my $supplied_col_info = $self->_resolve_column_info($source, [keys %$to_insert] ); |
ca791b95 |
76 | |
77 | my %guid_cols; |
78 | my @pk_cols = $source->primary_columns; |
79 | my %pk_cols; |
80 | @pk_cols{@pk_cols} = (); |
81 | |
82 | my @pk_guids = grep { |
be294d66 |
83 | $source->column_info($_)->{data_type} |
84 | && |
ca791b95 |
85 | $source->column_info($_)->{data_type} =~ /^uniqueidentifier/i |
86 | } @pk_cols; |
87 | |
88 | my @auto_guids = grep { |
be294d66 |
89 | $source->column_info($_)->{data_type} |
90 | && |
ca791b95 |
91 | $source->column_info($_)->{data_type} =~ /^uniqueidentifier/i |
92 | && |
93 | $source->column_info($_)->{auto_nextval} |
94 | } grep { not exists $pk_cols{$_} } $source->columns; |
95 | |
96 | my @get_guids_for = |
97 | grep { not exists $to_insert->{$_} } (@pk_guids, @auto_guids); |
98 | |
afcfff01 |
99 | my $updated_cols = {}; |
100 | |
ca791b95 |
101 | for my $guid_col (@get_guids_for) { |
9ae966b9 |
102 | my ($new_guid) = $self->_get_dbh->selectrow_array('SELECT NEWID()'); |
ca791b95 |
103 | $updated_cols->{$guid_col} = $to_insert->{$guid_col} = $new_guid; |
104 | } |
105 | |
aac1a358 |
106 | my $is_identity_insert = (List::Util::first { $_->{is_auto_increment} } (values %$supplied_col_info) ) |
107 | ? 1 |
108 | : 0; |
109 | |
110 | if ($is_identity_insert) { |
111 | $self->_set_identity_insert ($source->name); |
afcfff01 |
112 | } |
113 | |
ca791b95 |
114 | $updated_cols = { %$updated_cols, %{ $self->next::method(@_) } }; |
115 | |
aac1a358 |
116 | if ($is_identity_insert) { |
117 | $self->_unset_identity_insert ($source->name); |
118 | } |
119 | |
120 | |
ca791b95 |
121 | return $updated_cols; |
122 | } |
123 | |
5a77aa8b |
124 | sub _prep_for_execute { |
125 | my $self = shift; |
126 | my ($op, $extra_bind, $ident, $args) = @_; |
127 | |
128 | # cast MONEY values properly |
129 | if ($op eq 'insert' || $op eq 'update') { |
130 | my $fields = $args->[0]; |
5a77aa8b |
131 | |
132 | for my $col (keys %$fields) { |
1537084d |
133 | # $ident is a result source object with INSERT/UPDATE ops |
be294d66 |
134 | if ($ident->column_info ($col)->{data_type} |
135 | && |
136 | $ident->column_info ($col)->{data_type} =~ /^money\z/i) { |
5a77aa8b |
137 | my $val = $fields->{$col}; |
138 | $fields->{$col} = \['CAST(? AS MONEY)', [ $col => $val ]]; |
139 | } |
140 | } |
141 | } |
142 | |
143 | my ($sql, $bind) = $self->next::method (@_); |
144 | |
145 | if ($op eq 'insert') { |
146 | $sql .= ';SELECT SCOPE_IDENTITY()'; |
147 | |
5a77aa8b |
148 | } |
149 | |
150 | return ($sql, $bind); |
151 | } |
152 | |
153 | sub _execute { |
154 | my $self = shift; |
155 | my ($op) = @_; |
156 | |
157 | my ($rv, $sth, @bind) = $self->dbh_do($self->can('_dbh_execute'), @_); |
1537084d |
158 | |
5a77aa8b |
159 | if ($op eq 'insert') { |
5a77aa8b |
160 | |
1537084d |
161 | # this should bring back the result of SELECT SCOPE_IDENTITY() we tacked |
162 | # on in _prep_for_execute above |
4ffa5700 |
163 | my ($identity) = eval { $sth->fetchrow_array }; |
ed8de058 |
164 | |
1537084d |
165 | # SCOPE_IDENTITY failed, but we can do something else |
166 | if ( (! $identity) && $self->_identity_method) { |
167 | ($identity) = $self->_dbh->selectrow_array( |
168 | 'select ' . $self->_identity_method |
169 | ); |
170 | } |
7b1b2582 |
171 | |
1537084d |
172 | $self->_identity($identity); |
173 | $sth->finish; |
7b1b2582 |
174 | } |
175 | |
1537084d |
176 | return wantarray ? ($rv, $sth, @bind) : $rv; |
7b1b2582 |
177 | } |
5a77aa8b |
178 | |
7b1b2582 |
179 | sub last_insert_id { shift->_identity } |
5a77aa8b |
180 | |
f0bd60fc |
181 | # |
e74c68ce |
182 | # MSSQL is retarded wrt ordered subselects. One needs to add a TOP |
183 | # to *all* subqueries, but one also can't use TOP 100 PERCENT |
184 | # http://sqladvice.com/forums/permalink/18496/22931/ShowThread.aspx#22931 |
f0bd60fc |
185 | # |
186 | sub _select_args_to_query { |
187 | my $self = shift; |
188 | |
b8d88d9b |
189 | my ($sql, $prep_bind, @rest) = $self->next::method (@_); |
f0bd60fc |
190 | |
b8d88d9b |
191 | # see if this is an ordered subquery |
192 | my $attrs = $_[3]; |
c0748280 |
193 | if ( scalar $self->_parse_order_by ($attrs->{order_by}) ) { |
6de07ea3 |
194 | $self->throw_exception( |
d74f2da9 |
195 | 'An ordered subselect encountered - this is not safe! Please see "Ordered Subselects" in DBIx::Class::Storage::DBI::MSSQL |
69a8b315 |
196 | ') unless $attrs->{unsafe_subselect_ok}; |
e74c68ce |
197 | my $max = 2 ** 32; |
198 | $sql =~ s/^ \s* SELECT \s/SELECT TOP $max /xi; |
f0bd60fc |
199 | } |
200 | |
f0bd60fc |
201 | return wantarray |
17555a0c |
202 | ? ($sql, $prep_bind, @rest) |
203 | : \[ "($sql)", @$prep_bind ] |
f0bd60fc |
204 | ; |
205 | } |
206 | |
207 | |
4c0f4206 |
208 | # savepoint syntax is the same as in Sybase ASE |
209 | |
210 | sub _svp_begin { |
211 | my ($self, $name) = @_; |
212 | |
9ae966b9 |
213 | $self->_get_dbh->do("SAVE TRANSACTION $name"); |
4c0f4206 |
214 | } |
215 | |
216 | # A new SAVE TRANSACTION with the same name releases the previous one. |
217 | sub _svp_release { 1 } |
218 | |
219 | sub _svp_rollback { |
220 | my ($self, $name) = @_; |
221 | |
9ae966b9 |
222 | $self->_get_dbh->do("ROLLBACK TRANSACTION $name"); |
4c0f4206 |
223 | } |
224 | |
ed8de058 |
225 | sub build_datetime_parser { |
226 | my $self = shift; |
227 | my $type = "DateTime::Format::Strptime"; |
228 | eval "use ${type}"; |
229 | $self->throw_exception("Couldn't load ${type}: $@") if $@; |
eb0323df |
230 | return $type->new( pattern => '%Y-%m-%d %H:%M:%S' ); # %F %T |
231 | } |
232 | |
233 | sub sqlt_type { 'SQLServer' } |
234 | |
e76e7b5c |
235 | sub _get_mssql_version { |
236 | my $self = shift; |
237 | |
238 | my $data = $self->_get_dbh->selectrow_hashref('xp_msver ProductVersion'); |
239 | |
240 | if ($data->{Character_Value} =~ /^(\d+)\./) { |
241 | return $1; |
242 | } else { |
50772633 |
243 | $self->throw_exception(q{Your ProductVersion's Character_Value is missing or malformed!}); |
e76e7b5c |
244 | } |
245 | } |
246 | |
50772633 |
247 | sub sql_maker { |
248 | my $self = shift; |
eb0323df |
249 | |
50772633 |
250 | unless ($self->_sql_maker) { |
251 | unless ($self->{_sql_maker_opts}{limit_dialect}) { |
097c5167 |
252 | my $version = eval { $self->_get_mssql_version; } || 0; |
eb0323df |
253 | |
50772633 |
254 | $self->{_sql_maker_opts} = { |
255 | limit_dialect => ($version >= 9 ? 'RowNumberOver' : 'Top'), |
256 | %{$self->{_sql_maker_opts}||{}} |
257 | }; |
258 | } |
259 | |
260 | my $maker = $self->next::method (@_); |
261 | } |
e76e7b5c |
262 | |
50772633 |
263 | return $self->_sql_maker; |
ed8de058 |
264 | } |
3885cff6 |
265 | |
75d07914 |
266 | 1; |
3885cff6 |
267 | |
75d07914 |
268 | =head1 NAME |
3885cff6 |
269 | |
5a77aa8b |
270 | DBIx::Class::Storage::DBI::MSSQL - Base Class for Microsoft SQL Server support |
271 | in DBIx::Class |
3885cff6 |
272 | |
75d07914 |
273 | =head1 SYNOPSIS |
3885cff6 |
274 | |
5a77aa8b |
275 | This is the base class for Microsoft SQL Server support, used by |
276 | L<DBIx::Class::Storage::DBI::ODBC::Microsoft_SQL_Server> and |
277 | L<DBIx::Class::Storage::DBI::Sybase::Microsoft_SQL_Server>. |
eb0323df |
278 | |
5a77aa8b |
279 | =head1 IMPLEMENTATION NOTES |
eb0323df |
280 | |
fd05d10a |
281 | =head2 IDENTITY information |
282 | |
5a77aa8b |
283 | Microsoft SQL Server supports three methods of retrieving the IDENTITY |
284 | value for inserted row: IDENT_CURRENT, @@IDENTITY, and SCOPE_IDENTITY(). |
285 | SCOPE_IDENTITY is used here because it is the safest. However, it must |
286 | be called is the same execute statement, not just the same connection. |
eb0323df |
287 | |
5a77aa8b |
288 | So, this implementation appends a SELECT SCOPE_IDENTITY() statement |
289 | onto each INSERT to accommodate that requirement. |
eb0323df |
290 | |
7b1b2582 |
291 | C<SELECT @@IDENTITY> can also be used by issuing: |
292 | |
293 | $self->_identity_method('@@identity'); |
294 | |
08cdc412 |
295 | it will only be used if SCOPE_IDENTITY() fails. |
296 | |
297 | This is more dangerous, as inserting into a table with an on insert trigger that |
298 | inserts into another table with an identity will give erroneous results on |
299 | recent versions of SQL Server. |
7b1b2582 |
300 | |
c84189e1 |
301 | =head2 identity insert |
fd05d10a |
302 | |
303 | Be aware that we have tried to make things as simple as possible for our users. |
c84189e1 |
304 | For MSSQL that means that when a user tries to create a row, while supplying an |
305 | explicit value for an autoincrementing column, we will try to issue the |
306 | appropriate database call to make this possible, namely C<SET IDENTITY_INSERT |
307 | $table_name ON>. Unfortunately this operation in MSSQL requires the |
308 | C<db_ddladmin> privilege, which is normally not included in the standard |
309 | write-permissions. |
fd05d10a |
310 | |
d74f2da9 |
311 | =head2 Ordered Subselects |
6de07ea3 |
312 | |
d74f2da9 |
313 | If you attempted the following query (among many others) in Microsoft SQL |
314 | Server |
6de07ea3 |
315 | |
6de07ea3 |
316 | $rs->search ({}, { |
6de07ea3 |
317 | prefetch => 'relation', |
318 | rows => 2, |
319 | offset => 3, |
320 | }); |
321 | |
d74f2da9 |
322 | You may be surprised to receive an exception. The reason for this is a quirk |
323 | in the MSSQL engine itself, and sadly doesn't have a sensible workaround due |
324 | to the way DBIC is built. DBIC can do truly wonderful things with the aid of |
325 | subselects, and does so automatically when necessary. The list of situations |
326 | when a subselect is necessary is long and still changes often, so it can not |
327 | be exhaustively enumerated here. The general rule of thumb is a joined |
328 | L<has_many|DBIx::Class::Relationship/has_many> relationship with limit/group |
329 | applied to the left part of the join. |
330 | |
331 | In its "pursuit of standards" Microsft SQL Server goes to great lengths to |
332 | forbid the use of ordered subselects. This breaks a very useful group of |
333 | searches like "Give me things number 4 to 6 (ordered by name), and prefetch |
334 | all their relations, no matter how many". While there is a hack which fools |
335 | the syntax checker, the optimizer may B<still elect to break the subselect>. |
336 | Testing has determined that while such breakage does occur (the test suite |
337 | contains an explicit test which demonstrates the problem), it is relative |
338 | rare. The benefits of ordered subselects are on the other hand too great to be |
339 | outright disabled for MSSQL. |
6de07ea3 |
340 | |
341 | Thus compromise between usability and perfection is the MSSQL-specific |
69a8b315 |
342 | L<resultset attribute|DBIx::Class::ResultSet/ATTRIBUTES> C<unsafe_subselect_ok>. |
6de07ea3 |
343 | It is deliberately not possible to set this on the Storage level, as the user |
48580715 |
344 | should inspect (and preferably regression-test) the return of every such |
d74f2da9 |
345 | ResultSet individually. The example above would work if written like: |
346 | |
347 | $rs->search ({}, { |
69a8b315 |
348 | unsafe_subselect_ok => 1, |
d74f2da9 |
349 | prefetch => 'relation', |
350 | rows => 2, |
351 | offset => 3, |
352 | }); |
6de07ea3 |
353 | |
354 | If it is possible to rewrite the search() in a way that will avoid the need |
355 | for this flag - you are urged to do so. If DBIC internals insist that an |
d74f2da9 |
356 | ordered subselect is necessary for an operation, and you believe there is a |
48580715 |
357 | different/better way to get the same result - please file a bugreport. |
6de07ea3 |
358 | |
5a77aa8b |
359 | =head1 AUTHOR |
3885cff6 |
360 | |
5a77aa8b |
361 | See L<DBIx::Class/CONTRIBUTORS>. |
3885cff6 |
362 | |
75d07914 |
363 | =head1 LICENSE |
3885cff6 |
364 | |
75d07914 |
365 | You may distribute this code under the same terms as Perl itself. |
3885cff6 |
366 | |
75d07914 |
367 | =cut |