Commit | Line | Data |
c443438f |
1 | package #hide from PAUSE |
2 | DBIx::Class::Storage::DBIHacks; |
d28bb90d |
3 | |
4 | # |
5 | # This module contains code that should never have seen the light of day, |
6 | # does not belong in the Storage, or is otherwise unfit for public |
6a6394f1 |
7 | # display. The arrival of SQLA2 should immediately obsolete 90% of this |
d28bb90d |
8 | # |
9 | |
10 | use strict; |
11 | use warnings; |
12 | |
13 | use base 'DBIx::Class::Storage'; |
14 | use mro 'c3'; |
15 | |
6298a324 |
16 | use List::Util 'first'; |
17 | use Scalar::Util 'blessed'; |
ea5c7509 |
18 | use Sub::Name 'subname'; |
6298a324 |
19 | use namespace::clean; |
d28bb90d |
20 | |
21 | # |
052e8431 |
22 | # This code will remove non-selecting/non-restricting joins from |
4b1b5ea3 |
23 | # {from} specs, aiding the RDBMS query optimizer |
052e8431 |
24 | # |
25 | sub _prune_unused_joins { |
e1861c2c |
26 | my ($self, $attrs) = @_; |
ea95892e |
27 | |
e1861c2c |
28 | # only standard {from} specs are supported, and we could be disabled in general |
29 | return ($attrs->{from}, {}) unless ( |
30 | ref $attrs->{from} eq 'ARRAY' |
31 | and |
32 | @{$attrs->{from}} > 1 |
33 | and |
34 | ref $attrs->{from}[0] eq 'HASH' |
35 | and |
36 | ref $attrs->{from}[1] eq 'ARRAY' |
37 | and |
38 | $self->_use_join_optimizer |
39 | ); |
052e8431 |
40 | |
eb58c082 |
41 | my $orig_aliastypes = $self->_resolve_aliastypes_from_select_args($attrs); |
4b1b5ea3 |
42 | |
eb58c082 |
43 | my $new_aliastypes = { %$orig_aliastypes }; |
44 | |
45 | # we will be recreating this entirely |
46 | my @reclassify = 'joining'; |
97e130fa |
47 | |
4b1b5ea3 |
48 | # a grouped set will not be affected by amount of rows. Thus any |
eb58c082 |
49 | # purely multiplicator classifications can go |
50 | # (will be reintroduced below if needed by something else) |
51 | push @reclassify, qw(multiplying premultiplied) |
437a9cfa |
52 | if $attrs->{_force_prune_multiplying_joins} or $attrs->{group_by}; |
4b1b5ea3 |
53 | |
eb58c082 |
54 | # nuke what will be recalculated |
55 | delete @{$new_aliastypes}{@reclassify}; |
56 | |
e1861c2c |
57 | my @newfrom = $attrs->{from}[0]; # FROM head is always present |
052e8431 |
58 | |
eb58c082 |
59 | # recalculate what we need once the multipliers are potentially gone |
60 | # ignore premultiplies, since they do not add any value to anything |
a4812caa |
61 | my %need_joins; |
eb58c082 |
62 | for ( @{$new_aliastypes}{grep { $_ ne 'premultiplied' } keys %$new_aliastypes }) { |
a4812caa |
63 | # add all requested aliases |
64 | $need_joins{$_} = 1 for keys %$_; |
65 | |
66 | # add all their parents (as per joinpath which is an AoH { table => alias }) |
97e130fa |
67 | $need_joins{$_} = 1 for map { values %$_ } map { @{$_->{-parents}} } values %$_; |
a4812caa |
68 | } |
97e130fa |
69 | |
e1861c2c |
70 | for my $j (@{$attrs->{from}}[1..$#{$attrs->{from}}]) { |
539ffe87 |
71 | push @newfrom, $j if ( |
a6ef93cb |
72 | (! defined $j->[0]{-alias}) # legacy crap |
539ffe87 |
73 | || |
74 | $need_joins{$j->[0]{-alias}} |
75 | ); |
052e8431 |
76 | } |
77 | |
eb58c082 |
78 | # we have a new set of joiners - for everything we nuked pull the classification |
79 | # off the original stack |
80 | for my $ctype (@reclassify) { |
81 | $new_aliastypes->{$ctype} = { map |
82 | { $need_joins{$_} ? ( $_ => $orig_aliastypes->{$ctype}{$_} ) : () } |
83 | keys %{$orig_aliastypes->{$ctype}} |
84 | } |
85 | } |
86 | |
87 | return ( \@newfrom, $new_aliastypes ); |
052e8431 |
88 | } |
89 | |
052e8431 |
90 | # |
d28bb90d |
91 | # This is the code producing joined subqueries like: |
8273e845 |
92 | # SELECT me.*, other.* FROM ( SELECT me.* FROM ... ) JOIN other ON ... |
d28bb90d |
93 | # |
94 | sub _adjust_select_args_for_complex_prefetch { |
e1861c2c |
95 | my ($self, $attrs) = @_; |
d28bb90d |
96 | |
e1861c2c |
97 | $self->throw_exception ('Complex prefetches are not supported on resultsets with a custom from attribute') unless ( |
98 | ref $attrs->{from} eq 'ARRAY' |
99 | and |
100 | @{$attrs->{from}} > 1 |
101 | and |
102 | ref $attrs->{from}[0] eq 'HASH' |
103 | and |
104 | ref $attrs->{from}[1] eq 'ARRAY' |
105 | ); |
d28bb90d |
106 | |
1e4f9fb3 |
107 | my $root_alias = $attrs->{alias}; |
108 | |
d28bb90d |
109 | # generate inner/outer attribute lists, remove stuff that doesn't apply |
110 | my $outer_attrs = { %$attrs }; |
e1861c2c |
111 | delete @{$outer_attrs}{qw(from bind rows offset group_by _grouped_by_distinct having)}; |
d28bb90d |
112 | |
186ba34c |
113 | my $inner_attrs = { %$attrs }; |
e1861c2c |
114 | delete @{$inner_attrs}{qw(for collapse select as _related_results_construction)}; |
d28bb90d |
115 | |
4df1400e |
116 | # there is no point of ordering the insides if there is no limit |
117 | delete $inner_attrs->{order_by} if ( |
118 | delete $inner_attrs->{_order_is_artificial} |
119 | or |
120 | ! $inner_attrs->{rows} |
121 | ); |
946f6260 |
122 | |
d28bb90d |
123 | # generate the inner/outer select lists |
124 | # for inside we consider only stuff *not* brought in by the prefetch |
125 | # on the outside we substitute any function for its alias |
e1861c2c |
126 | $outer_attrs->{select} = [ @{$attrs->{select}} ]; |
36fd7f07 |
127 | |
97e130fa |
128 | my ($root_node, $root_node_offset); |
27e0370d |
129 | |
e1861c2c |
130 | for my $i (0 .. $#{$inner_attrs->{from}}) { |
131 | my $node = $inner_attrs->{from}[$i]; |
27e0370d |
132 | my $h = (ref $node eq 'HASH') ? $node |
133 | : (ref $node eq 'ARRAY' and ref $node->[0] eq 'HASH') ? $node->[0] |
134 | : next |
135 | ; |
136 | |
1e4f9fb3 |
137 | if ( ($h->{-alias}||'') eq $root_alias and $h->{-rsrc} ) { |
97e130fa |
138 | $root_node = $h; |
139 | $root_node_offset = $i; |
27e0370d |
140 | last; |
141 | } |
142 | } |
143 | |
144 | $self->throw_exception ('Complex prefetches are not supported on resultsets with a custom from attribute') |
97e130fa |
145 | unless $root_node; |
27e0370d |
146 | |
147 | # use the heavy duty resolver to take care of aliased/nonaliased naming |
e1861c2c |
148 | my $colinfo = $self->_resolve_column_info($inner_attrs->{from}); |
27e0370d |
149 | my $selected_root_columns; |
150 | |
e1861c2c |
151 | for my $i (0 .. $#{$outer_attrs->{select}}) { |
152 | my $sel = $outer_attrs->{select}->[$i]; |
d28bb90d |
153 | |
1e4f9fb3 |
154 | next if ( |
155 | $colinfo->{$sel} and $colinfo->{$sel}{-source_alias} ne $root_alias |
156 | ); |
157 | |
d28bb90d |
158 | if (ref $sel eq 'HASH' ) { |
159 | $sel->{-as} ||= $attrs->{as}[$i]; |
e1861c2c |
160 | $outer_attrs->{select}->[$i] = join ('.', $root_alias, ($sel->{-as} || "inner_column_$i") ); |
d28bb90d |
161 | } |
27e0370d |
162 | elsif (! ref $sel and my $ci = $colinfo->{$sel}) { |
163 | $selected_root_columns->{$ci->{-colname}} = 1; |
164 | } |
d28bb90d |
165 | |
e1861c2c |
166 | push @{$inner_attrs->{select}}, $sel; |
bb9bffea |
167 | |
168 | push @{$inner_attrs->{as}}, $attrs->{as}[$i]; |
d28bb90d |
169 | } |
170 | |
97e130fa |
171 | # We will need to fetch all native columns in the inner subquery, which may |
172 | # be a part of an *outer* join condition, or an order_by (which needs to be |
e1861c2c |
173 | # preserved outside), or wheres. In other words everything but the inner |
174 | # selector |
97e130fa |
175 | # We can not just fetch everything because a potential has_many restricting |
176 | # join collapse *will not work* on heavy data types. |
e1861c2c |
177 | my $connecting_aliastypes = $self->_resolve_aliastypes_from_select_args({ |
178 | %$inner_attrs, |
179 | select => [], |
180 | }); |
97e130fa |
181 | |
182 | for (sort map { keys %{$_->{-seen_columns}||{}} } map { values %$_ } values %$connecting_aliastypes) { |
183 | my $ci = $colinfo->{$_} or next; |
184 | if ( |
1e4f9fb3 |
185 | $ci->{-source_alias} eq $root_alias |
97e130fa |
186 | and |
187 | ! $selected_root_columns->{$ci->{-colname}}++ |
188 | ) { |
189 | # adding it to both to keep limits not supporting dark selectors happy |
e1861c2c |
190 | push @{$inner_attrs->{select}}, $ci->{-fq_colname}; |
97e130fa |
191 | push @{$inner_attrs->{as}}, $ci->{-fq_colname}; |
27e0370d |
192 | } |
193 | } |
194 | |
e1861c2c |
195 | # construct the inner {from} and lock it in a subquery |
48580715 |
196 | # we need to prune first, because this will determine if we need a group_by below |
97e130fa |
197 | # throw away all non-selecting, non-restricting multijoins |
eb58c082 |
198 | # (since we def. do not care about multiplication of the contents of the subquery) |
6395604e |
199 | my $inner_subq = do { |
ea95892e |
200 | |
eb58c082 |
201 | # must use it here regardless of user requests (vastly gentler on optimizer) |
ea95892e |
202 | local $self->{_use_join_optimizer} = 1; |
203 | |
97e130fa |
204 | # throw away multijoins since we def. do not care about those inside the subquery |
e1861c2c |
205 | ($inner_attrs->{from}, my $inner_aliastypes) = $self->_prune_unused_joins ({ |
437a9cfa |
206 | %$inner_attrs, _force_prune_multiplying_joins => 1 |
207 | }); |
ea95892e |
208 | |
eb58c082 |
209 | # uh-oh a multiplier (which is not us) left in, this is a problem for limits |
210 | # we will need to add a group_by to collapse the resultset for proper counts |
0a3441ee |
211 | if ( |
eb58c082 |
212 | grep { $_ ne $root_alias } keys %{ $inner_aliastypes->{multiplying} || {} } |
1e4f9fb3 |
213 | and |
560978e2 |
214 | # if there are user-supplied groups - assume user knows wtf they are up to |
215 | ( ! $inner_aliastypes->{grouping} or $inner_attrs->{_grouped_by_distinct} ) |
0a3441ee |
216 | ) { |
1e4f9fb3 |
217 | |
eb58c082 |
218 | my $cur_sel = { map { $_ => 1 } @{$inner_attrs->{select}} }; |
1e4f9fb3 |
219 | |
eb58c082 |
220 | # *possibly* supplement the main selection with pks if not already |
221 | # there, as they will have to be a part of the group_by to collapse |
222 | # things properly |
223 | my $inner_select_with_extras; |
224 | my @pks = map { "$root_alias.$_" } $root_node->{-rsrc}->primary_columns |
225 | or $self->throw_exception( sprintf |
226 | 'Unable to perform complex limited prefetch off %s without declared primary key', |
227 | $root_node->{-rsrc}->source_name, |
e1861c2c |
228 | ); |
eb58c082 |
229 | for my $col (@pks) { |
230 | push @{ $inner_select_with_extras ||= [ @{$inner_attrs->{select}} ] }, $col |
231 | unless $cur_sel->{$col}++; |
1e4f9fb3 |
232 | } |
eb58c082 |
233 | |
234 | ($inner_attrs->{group_by}, $inner_attrs->{order_by}) = $self->_group_over_selection({ |
235 | %$inner_attrs, |
236 | $inner_select_with_extras ? ( select => $inner_select_with_extras ) : (), |
237 | _aliastypes => $inner_aliastypes, |
238 | }); |
0a3441ee |
239 | } |
d28bb90d |
240 | |
e1861c2c |
241 | # we already optimized $inner_attrs->{from} above |
97e130fa |
242 | # and already local()ized |
243 | $self->{_use_join_optimizer} = 0; |
d28bb90d |
244 | |
ea95892e |
245 | # generate the subquery |
6395604e |
246 | $self->_select_args_to_query ( |
e1861c2c |
247 | @{$inner_attrs}{qw(from select where)}, |
ea95892e |
248 | $inner_attrs, |
249 | ); |
d28bb90d |
250 | }; |
251 | |
252 | # Generate the outer from - this is relatively easy (really just replace |
253 | # the join slot with the subquery), with a major caveat - we can not |
254 | # join anything that is non-selecting (not part of the prefetch), but at |
255 | # the same time is a multi-type relationship, as it will explode the result. |
256 | # |
257 | # There are two possibilities here |
258 | # - either the join is non-restricting, in which case we simply throw it away |
259 | # - it is part of the restrictions, in which case we need to collapse the outer |
260 | # result by tackling yet another group_by to the outside of the query |
261 | |
27e0370d |
262 | # work on a shallow copy |
e1861c2c |
263 | my @orig_from = @{$attrs->{from}}; |
264 | |
052e8431 |
265 | |
e1861c2c |
266 | $outer_attrs->{from} = \ my @outer_from; |
53c29913 |
267 | |
27e0370d |
268 | # we may not be the head |
97e130fa |
269 | if ($root_node_offset) { |
e1861c2c |
270 | # first generate the outer_from, up to the substitution point |
271 | @outer_from = splice @orig_from, 0, $root_node_offset; |
27e0370d |
272 | |
e1861c2c |
273 | # substitute the subq at the right spot |
27e0370d |
274 | push @outer_from, [ |
275 | { |
1e4f9fb3 |
276 | -alias => $root_alias, |
97e130fa |
277 | -rsrc => $root_node->{-rsrc}, |
1e4f9fb3 |
278 | $root_alias => $inner_subq, |
27e0370d |
279 | }, |
e1861c2c |
280 | # preserve attrs from what is now the head of the from after the splice |
281 | @{$orig_from[0]}[1 .. $#{$orig_from[0]}], |
27e0370d |
282 | ]; |
283 | } |
284 | else { |
27e0370d |
285 | @outer_from = { |
1e4f9fb3 |
286 | -alias => $root_alias, |
27e0370d |
287 | -rsrc => $root_node->{-rsrc}, |
1e4f9fb3 |
288 | $root_alias => $inner_subq, |
27e0370d |
289 | }; |
d28bb90d |
290 | } |
291 | |
e1861c2c |
292 | shift @orig_from; # what we just replaced above |
97e130fa |
293 | |
ea95892e |
294 | # scan the *remaining* from spec against different attributes, and see which joins are needed |
052e8431 |
295 | # in what role |
975b573a |
296 | my $outer_aliastypes = $outer_attrs->{_aliastypes} = |
e1861c2c |
297 | $self->_resolve_aliastypes_from_select_args({ %$outer_attrs, from => \@orig_from }); |
052e8431 |
298 | |
a4812caa |
299 | # unroll parents |
1e4f9fb3 |
300 | my ($outer_select_chain, @outer_nonselecting_chains) = map { +{ |
301 | map { $_ => 1 } map { values %$_} map { @{$_->{-parents}} } values %{ $outer_aliastypes->{$_} || {} } |
302 | } } qw/selecting restricting grouping ordering/; |
a4812caa |
303 | |
d28bb90d |
304 | # see what's left - throw away if not selecting/restricting |
eb58c082 |
305 | my $may_need_outer_group_by; |
e1861c2c |
306 | while (my $j = shift @orig_from) { |
d28bb90d |
307 | my $alias = $j->[0]{-alias}; |
308 | |
a4812caa |
309 | if ( |
310 | $outer_select_chain->{$alias} |
311 | ) { |
312 | push @outer_from, $j |
d28bb90d |
313 | } |
1e4f9fb3 |
314 | elsif (first { $_->{$alias} } @outer_nonselecting_chains ) { |
d28bb90d |
315 | push @outer_from, $j; |
eb58c082 |
316 | $may_need_outer_group_by ||= $outer_aliastypes->{multiplying}{$alias} ? 1 : 0; |
d28bb90d |
317 | } |
318 | } |
319 | |
eb58c082 |
320 | # also throw in a synthetic group_by if a non-selecting multiplier, |
321 | # to guard against cross-join explosions |
322 | # the logic is somewhat fragile, but relies on the idea that if a user supplied |
323 | # a group by on their own - they know what they were doing |
324 | if ( $may_need_outer_group_by and $attrs->{_grouped_by_distinct} ) { |
325 | ($outer_attrs->{group_by}, $outer_attrs->{order_by}) = $self->_group_over_selection ({ |
560978e2 |
326 | %$outer_attrs, |
327 | from => \@outer_from, |
560978e2 |
328 | }); |
36fd7f07 |
329 | } |
330 | |
e1861c2c |
331 | # This is totally horrific - the {where} ends up in both the inner and outer query |
d28bb90d |
332 | # Unfortunately not much can be done until SQLA2 introspection arrives, and even |
333 | # then if where conditions apply to the *right* side of the prefetch, you may have |
334 | # to both filter the inner select (e.g. to apply a limit) and then have to re-filter |
4a0eed52 |
335 | # the outer select to exclude joins you didn't want in the first place |
d28bb90d |
336 | # |
337 | # OTOH it can be seen as a plus: <ash> (notes that this query would make a DBA cry ;) |
e1861c2c |
338 | return $outer_attrs; |
d28bb90d |
339 | } |
340 | |
1a736efb |
341 | # |
342 | # I KNOW THIS SUCKS! GET SQLA2 OUT THE DOOR SO THIS CAN DIE! |
343 | # |
ad630f4b |
344 | # Due to a lack of SQLA2 we fall back to crude scans of all the |
345 | # select/where/order/group attributes, in order to determine what |
4a0eed52 |
346 | # aliases are needed to fulfill the query. This information is used |
ad630f4b |
347 | # throughout the code to prune unnecessary JOINs from the queries |
348 | # in an attempt to reduce the execution time. |
349 | # Although the method is pretty horrific, the worst thing that can |
1a736efb |
350 | # happen is for it to fail due to some scalar SQL, which in turn will |
351 | # result in a vocal exception. |
539ffe87 |
352 | sub _resolve_aliastypes_from_select_args { |
e1861c2c |
353 | my ( $self, $attrs ) = @_; |
546f1cd9 |
354 | |
ad630f4b |
355 | $self->throw_exception ('Unable to analyze custom {from}') |
e1861c2c |
356 | if ref $attrs->{from} ne 'ARRAY'; |
546f1cd9 |
357 | |
ad630f4b |
358 | # what we will return |
964a3c71 |
359 | my $aliases_by_type; |
546f1cd9 |
360 | |
ad630f4b |
361 | # see what aliases are there to work with |
eb58c082 |
362 | # and record who is a multiplier and who is premultiplied |
ad630f4b |
363 | my $alias_list; |
e1861c2c |
364 | for my $node (@{$attrs->{from}}) { |
365 | |
366 | my $j = $node; |
ad630f4b |
367 | $j = $j->[0] if ref $j eq 'ARRAY'; |
539ffe87 |
368 | my $al = $j->{-alias} |
369 | or next; |
370 | |
371 | $alias_list->{$al} = $j; |
eb58c082 |
372 | |
373 | $aliases_by_type->{multiplying}{$al} ||= { -parents => $j->{-join_path}||[] } |
a4812caa |
374 | # not array == {from} head == can't be multiplying |
eb58c082 |
375 | if ref($node) eq 'ARRAY' and ! $j->{-is_single}; |
376 | |
377 | $aliases_by_type->{premultiplied}{$al} ||= { -parents => $j->{-join_path}||[] } |
378 | # parts of the path that are not us but are multiplying |
379 | if grep { $aliases_by_type->{multiplying}{$_} } |
380 | grep { $_ ne $al } |
381 | map { values %$_ } |
382 | @{ $j->{-join_path}||[] } |
546f1cd9 |
383 | } |
546f1cd9 |
384 | |
318e3d94 |
385 | # get a column to source/alias map (including unambiguous unqualified ones) |
e1861c2c |
386 | my $colinfo = $self->_resolve_column_info ($attrs->{from}); |
1a736efb |
387 | |
ad630f4b |
388 | # set up a botched SQLA |
389 | my $sql_maker = $self->sql_maker; |
07f31d19 |
390 | |
4c2b30d6 |
391 | # these are throw away results, do not pollute the bind stack |
4c2b30d6 |
392 | local $sql_maker->{select_bind}; |
0542ec57 |
393 | local $sql_maker->{where_bind}; |
394 | local $sql_maker->{group_bind}; |
395 | local $sql_maker->{having_bind}; |
97e130fa |
396 | local $sql_maker->{from_bind}; |
3f5b99fe |
397 | |
398 | # we can't scan properly without any quoting (\b doesn't cut it |
399 | # everywhere), so unless there is proper quoting set - use our |
400 | # own weird impossible character. |
401 | # Also in the case of no quoting, we need to explicitly disable |
402 | # name_sep, otherwise sorry nasty legacy syntax like |
403 | # { 'count(foo.id)' => { '>' => 3 } } will stop working >:( |
404 | local $sql_maker->{quote_char} = $sql_maker->{quote_char}; |
405 | local $sql_maker->{name_sep} = $sql_maker->{name_sep}; |
406 | |
407 | unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) { |
e493ecb2 |
408 | $sql_maker->{quote_char} = ["\x00", "\xFF"]; |
409 | # if we don't unset it we screw up retarded but unfortunately working |
410 | # 'MAX(foo.bar)' => { '>', 3 } |
3f5b99fe |
411 | $sql_maker->{name_sep} = ''; |
412 | } |
413 | |
414 | my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep); |
07f31d19 |
415 | |
1a736efb |
416 | # generate sql chunks |
417 | my $to_scan = { |
418 | restricting => [ |
e1861c2c |
419 | $sql_maker->_recurse_where ($attrs->{where}), |
1e4f9fb3 |
420 | $sql_maker->_parse_rs_attrs ({ having => $attrs->{having} }), |
421 | ], |
422 | grouping => [ |
423 | $sql_maker->_parse_rs_attrs ({ group_by => $attrs->{group_by} }), |
1a736efb |
424 | ], |
97e130fa |
425 | joining => [ |
426 | $sql_maker->_recurse_from ( |
e1861c2c |
427 | ref $attrs->{from}[0] eq 'ARRAY' ? $attrs->{from}[0][0] : $attrs->{from}[0], |
428 | @{$attrs->{from}}[1 .. $#{$attrs->{from}}], |
97e130fa |
429 | ), |
430 | ], |
1a736efb |
431 | selecting => [ |
0dadd60d |
432 | map { $sql_maker->_recurse_fields($_) } @{$attrs->{select}}, |
1e4f9fb3 |
433 | ], |
434 | ordering => [ |
435 | map { $_->[0] } $self->_extract_order_criteria ($attrs->{order_by}, $sql_maker), |
1a736efb |
436 | ], |
437 | }; |
07f31d19 |
438 | |
0dadd60d |
439 | # throw away empty chunks and all 2-value arrayrefs: the thinking is that these are |
440 | # bind value specs left in by the sloppy renderer above. It is ok to do this |
441 | # at this point, since we are going to end up rewriting this crap anyway |
442 | for my $v (values %$to_scan) { |
443 | my @nv; |
444 | for (@$v) { |
445 | next if ( |
446 | ! defined $_ |
447 | or |
448 | ( |
449 | ref $_ eq 'ARRAY' |
450 | and |
451 | ( @$_ == 0 or @$_ == 2 ) |
452 | ) |
453 | ); |
454 | |
455 | if (ref $_) { |
456 | require Data::Dumper::Concise; |
457 | $self->throw_exception("Unexpected ref in scan-plan: " . Data::Dumper::Concise::Dumper($v) ); |
458 | } |
459 | |
460 | push @nv, $_; |
461 | } |
462 | |
463 | $v = \@nv; |
464 | } |
465 | |
466 | # kill all selectors which look like a proper subquery |
467 | # this is a sucky heuristic *BUT* - if we get it wrong the query will simply |
468 | # fail to run, so we are relatively safe |
469 | $to_scan->{selecting} = [ grep { |
470 | $_ !~ / \A \s* \( \s* SELECT \s+ .+? \s+ FROM \s+ .+? \) \s* \z /xsi |
471 | } @{ $to_scan->{selecting} || [] } ]; |
07f31d19 |
472 | |
318e3d94 |
473 | # first see if we have any exact matches (qualified or unqualified) |
474 | for my $type (keys %$to_scan) { |
475 | for my $piece (@{$to_scan->{$type}}) { |
476 | if ($colinfo->{$piece} and my $alias = $colinfo->{$piece}{-source_alias}) { |
477 | $aliases_by_type->{$type}{$alias} ||= { -parents => $alias_list->{$alias}{-join_path}||[] }; |
478 | $aliases_by_type->{$type}{$alias}{-seen_columns}{$colinfo->{$piece}{-fq_colname}} = $piece; |
479 | } |
480 | } |
481 | } |
482 | |
483 | # now loop through all fully qualified columns and get the corresponding |
1a736efb |
484 | # alias (should work even if they are in scalarrefs) |
ad630f4b |
485 | for my $alias (keys %$alias_list) { |
1a736efb |
486 | my $al_re = qr/ |
97e130fa |
487 | $lquote $alias $rquote $sep (?: $lquote ([^$rquote]+) $rquote )? |
1a736efb |
488 | | |
97e130fa |
489 | \b $alias \. ([^\s\)\($rquote]+)? |
1a736efb |
490 | /x; |
491 | |
1a736efb |
492 | for my $type (keys %$to_scan) { |
493 | for my $piece (@{$to_scan->{$type}}) { |
97e130fa |
494 | if (my @matches = $piece =~ /$al_re/g) { |
495 | $aliases_by_type->{$type}{$alias} ||= { -parents => $alias_list->{$alias}{-join_path}||[] }; |
1e4f9fb3 |
496 | $aliases_by_type->{$type}{$alias}{-seen_columns}{"$alias.$_"} = "$alias.$_" |
97e130fa |
497 | for grep { defined $_ } @matches; |
498 | } |
1a736efb |
499 | } |
ad630f4b |
500 | } |
1a736efb |
501 | } |
502 | |
503 | # now loop through unqualified column names, and try to locate them within |
504 | # the chunks |
505 | for my $col (keys %$colinfo) { |
3f5b99fe |
506 | next if $col =~ / \. /x; # if column is qualified it was caught by the above |
1a736efb |
507 | |
97e130fa |
508 | my $col_re = qr/ $lquote ($col) $rquote /x; |
07f31d19 |
509 | |
1a736efb |
510 | for my $type (keys %$to_scan) { |
511 | for my $piece (@{$to_scan->{$type}}) { |
318e3d94 |
512 | if ( my @matches = $piece =~ /$col_re/g) { |
a4812caa |
513 | my $alias = $colinfo->{$col}{-source_alias}; |
97e130fa |
514 | $aliases_by_type->{$type}{$alias} ||= { -parents => $alias_list->{$alias}{-join_path}||[] }; |
1e4f9fb3 |
515 | $aliases_by_type->{$type}{$alias}{-seen_columns}{"$alias.$_"} = $_ |
97e130fa |
516 | for grep { defined $_ } @matches; |
a4812caa |
517 | } |
1a736efb |
518 | } |
07f31d19 |
519 | } |
520 | } |
521 | |
522 | # Add any non-left joins to the restriction list (such joins are indeed restrictions) |
ad630f4b |
523 | for my $j (values %$alias_list) { |
07f31d19 |
524 | my $alias = $j->{-alias} or next; |
97e130fa |
525 | $aliases_by_type->{restricting}{$alias} ||= { -parents => $j->{-join_path}||[] } if ( |
07f31d19 |
526 | (not $j->{-join_type}) |
527 | or |
528 | ($j->{-join_type} !~ /^left (?: \s+ outer)? $/xi) |
529 | ); |
530 | } |
531 | |
1e4f9fb3 |
532 | for (keys %$aliases_by_type) { |
533 | delete $aliases_by_type->{$_} unless keys %{$aliases_by_type->{$_}}; |
534 | } |
535 | |
964a3c71 |
536 | return $aliases_by_type; |
07f31d19 |
537 | } |
538 | |
eb58c082 |
539 | # This is the engine behind { distinct => 1 } and the general |
540 | # complex prefetch grouper |
0a3441ee |
541 | sub _group_over_selection { |
560978e2 |
542 | my ($self, $attrs) = @_; |
0a3441ee |
543 | |
560978e2 |
544 | my $colinfos = $self->_resolve_column_info ($attrs->{from}); |
0a3441ee |
545 | |
546 | my (@group_by, %group_index); |
547 | |
36fd7f07 |
548 | # the logic is: if it is a { func => val } we assume an aggregate, |
549 | # otherwise if \'...' or \[...] we assume the user knows what is |
550 | # going on thus group over it |
560978e2 |
551 | for (@{$attrs->{select}}) { |
0a3441ee |
552 | if (! ref($_) or ref ($_) ne 'HASH' ) { |
553 | push @group_by, $_; |
554 | $group_index{$_}++; |
560978e2 |
555 | if ($colinfos->{$_} and $_ !~ /\./ ) { |
0a3441ee |
556 | # add a fully qualified version as well |
560978e2 |
557 | $group_index{"$colinfos->{$_}{-source_alias}.$_"}++; |
0a3441ee |
558 | } |
07f31d19 |
559 | } |
560 | } |
ad630f4b |
561 | |
eb58c082 |
562 | my @order_by = $self->_extract_order_criteria($attrs->{order_by}) |
563 | or return (\@group_by, $attrs->{order_by}); |
564 | |
565 | # add any order_by parts that are not already present in the group_by |
566 | # to maintain SQL cross-compatibility and general sanity |
567 | # |
568 | # also in case the original selection is *not* unique, or in case part |
569 | # of the ORDER BY refers to a multiplier - we will need to replace the |
570 | # skipped order_by elements with their MIN/MAX equivalents as to maintain |
571 | # the proper overall order without polluting the group criteria (and |
572 | # possibly changing the outcome entirely) |
573 | |
574 | my ($leftovers, $sql_maker, @new_order_by, $order_chunks, $aliastypes); |
575 | |
576 | my $group_already_unique = $self->_columns_comprise_identifying_set($colinfos, \@group_by); |
577 | |
578 | for my $o_idx (0 .. $#order_by) { |
579 | |
580 | # if the chunk is already a min/max function - there is nothing left to touch |
581 | next if $order_by[$o_idx][0] =~ /^ (?: min | max ) \s* \( .+ \) $/ix; |
582 | |
0a3441ee |
583 | # only consider real columns (for functions the user got to do an explicit group_by) |
eb58c082 |
584 | my $chunk_ci; |
585 | if ( |
586 | @{$order_by[$o_idx]} != 1 |
587 | or |
588 | # only declare an unknown *plain* identifier as "leftover" if we are called with |
589 | # aliastypes to examine. If there are none - we are still in _resolve_attrs, and |
590 | # can just assume the user knows what they want |
591 | ( ! ( $chunk_ci = $colinfos->{$order_by[$o_idx][0]} ) and $attrs->{_aliastypes} ) |
592 | ) { |
593 | push @$leftovers, $order_by[$o_idx][0]; |
14e26c5f |
594 | } |
560978e2 |
595 | |
eb58c082 |
596 | next unless $chunk_ci; |
597 | |
598 | # no duplication of group criteria |
599 | next if $group_index{$chunk_ci->{-fq_colname}}; |
600 | |
601 | $aliastypes ||= ( |
602 | $attrs->{_aliastypes} |
560978e2 |
603 | or |
eb58c082 |
604 | $self->_resolve_aliastypes_from_select_args({ |
605 | from => $attrs->{from}, |
606 | order_by => $attrs->{order_by}, |
607 | }) |
608 | ) if $group_already_unique; |
609 | |
610 | # check that we are not ordering by a multiplier (if a check is requested at all) |
611 | if ( |
612 | $group_already_unique |
613 | and |
614 | ! $aliastypes->{multiplying}{$chunk_ci->{-source_alias}} |
615 | and |
616 | ! $aliastypes->{premultiplied}{$chunk_ci->{-source_alias}} |
560978e2 |
617 | ) { |
eb58c082 |
618 | push @group_by, $chunk_ci->{-fq_colname}; |
619 | $group_index{$chunk_ci->{-fq_colname}}++ |
560978e2 |
620 | } |
eb58c082 |
621 | else { |
622 | # We need to order by external columns without adding them to the group |
623 | # (eiehter a non-unique selection, or a multi-external) |
624 | # |
625 | # This doesn't really make sense in SQL, however from DBICs point |
626 | # of view is rather valid (e.g. order the leftmost objects by whatever |
627 | # criteria and get the offset/rows many). There is a way around |
628 | # this however in SQL - we simply tae the direction of each piece |
629 | # of the external order and convert them to MIN(X) for ASC or MAX(X) |
630 | # for DESC, and group_by the root columns. The end result should be |
631 | # exactly what we expect |
632 | |
633 | # FIXME - this code is a joke, will need to be completely rewritten in |
634 | # the DQ branch. But I need to push a POC here, otherwise the |
635 | # pesky tests won't pass |
636 | # wrap any part of the order_by that "responds" to an ordering alias |
637 | # into a MIN/MAX |
638 | $sql_maker ||= $self->sql_maker; |
639 | $order_chunks ||= [ |
640 | map { ref $_ eq 'ARRAY' ? $_ : [ $_ ] } $sql_maker->_order_by_chunks($attrs->{order_by}) |
641 | ]; |
0a3441ee |
642 | |
eb58c082 |
643 | my ($chunk, $is_desc) = $sql_maker->_split_order_chunk($order_chunks->[$o_idx][0]); |
644 | |
645 | $new_order_by[$o_idx] = \[ |
646 | sprintf( '%s( %s )%s', |
647 | ($is_desc ? 'MAX' : 'MIN'), |
648 | $chunk, |
649 | ($is_desc ? ' DESC' : ''), |
650 | ), |
651 | @ {$order_chunks->[$o_idx]} [ 1 .. $#{$order_chunks->[$o_idx]} ] |
652 | ]; |
653 | } |
0a3441ee |
654 | } |
655 | |
eb58c082 |
656 | $self->throw_exception ( sprintf |
657 | 'A required group_by clause could not be constructed automatically due to a complex ' |
658 | . 'order_by criteria (%s). Either order_by columns only (no functions) or construct a suitable ' |
659 | . 'group_by by hand', |
660 | join ', ', map { "'$_'" } @$leftovers, |
661 | ) if $leftovers; |
662 | |
663 | # recreate the untouched order parts |
664 | if (@new_order_by) { |
665 | $new_order_by[$_] ||= \ $order_chunks->[$_] for ( 0 .. $#$order_chunks ); |
666 | } |
667 | |
668 | return ( |
669 | \@group_by, |
670 | (@new_order_by ? \@new_order_by : $attrs->{order_by} ), # same ref as original == unchanged |
671 | ); |
07f31d19 |
672 | } |
673 | |
d28bb90d |
674 | sub _resolve_ident_sources { |
675 | my ($self, $ident) = @_; |
676 | |
677 | my $alias2source = {}; |
d28bb90d |
678 | |
679 | # the reason this is so contrived is that $ident may be a {from} |
680 | # structure, specifying multiple tables to join |
6298a324 |
681 | if ( blessed $ident && $ident->isa("DBIx::Class::ResultSource") ) { |
d28bb90d |
682 | # this is compat mode for insert/update/delete which do not deal with aliases |
683 | $alias2source->{me} = $ident; |
d28bb90d |
684 | } |
685 | elsif (ref $ident eq 'ARRAY') { |
686 | |
687 | for (@$ident) { |
688 | my $tabinfo; |
689 | if (ref $_ eq 'HASH') { |
690 | $tabinfo = $_; |
d28bb90d |
691 | } |
692 | if (ref $_ eq 'ARRAY' and ref $_->[0] eq 'HASH') { |
693 | $tabinfo = $_->[0]; |
694 | } |
695 | |
4376a157 |
696 | $alias2source->{$tabinfo->{-alias}} = $tabinfo->{-rsrc} |
697 | if ($tabinfo->{-rsrc}); |
d28bb90d |
698 | } |
699 | } |
700 | |
90f10b5a |
701 | return $alias2source; |
d28bb90d |
702 | } |
703 | |
704 | # Takes $ident, \@column_names |
705 | # |
706 | # returns { $column_name => \%column_info, ... } |
707 | # also note: this adds -result_source => $rsrc to the column info |
708 | # |
09e14fdc |
709 | # If no columns_names are supplied returns info about *all* columns |
710 | # for all sources |
d28bb90d |
711 | sub _resolve_column_info { |
712 | my ($self, $ident, $colnames) = @_; |
90f10b5a |
713 | my $alias2src = $self->_resolve_ident_sources($ident); |
d28bb90d |
714 | |
52416317 |
715 | my (%seen_cols, @auto_colnames); |
d28bb90d |
716 | |
717 | # compile a global list of column names, to be able to properly |
718 | # disambiguate unqualified column names (if at all possible) |
719 | for my $alias (keys %$alias2src) { |
720 | my $rsrc = $alias2src->{$alias}; |
721 | for my $colname ($rsrc->columns) { |
722 | push @{$seen_cols{$colname}}, $alias; |
3f5b99fe |
723 | push @auto_colnames, "$alias.$colname" unless $colnames; |
d28bb90d |
724 | } |
725 | } |
726 | |
09e14fdc |
727 | $colnames ||= [ |
728 | @auto_colnames, |
729 | grep { @{$seen_cols{$_}} == 1 } (keys %seen_cols), |
730 | ]; |
731 | |
52416317 |
732 | my (%return, $colinfos); |
d28bb90d |
733 | foreach my $col (@$colnames) { |
52416317 |
734 | my ($source_alias, $colname) = $col =~ m/^ (?: ([^\.]+) \. )? (.+) $/x; |
d28bb90d |
735 | |
52416317 |
736 | # if the column was seen exactly once - we know which rsrc it came from |
737 | $source_alias ||= $seen_cols{$colname}[0] |
738 | if ($seen_cols{$colname} and @{$seen_cols{$colname}} == 1); |
d28bb90d |
739 | |
52416317 |
740 | next unless $source_alias; |
741 | |
742 | my $rsrc = $alias2src->{$source_alias} |
743 | or next; |
744 | |
745 | $return{$col} = { |
6395604e |
746 | %{ |
747 | ( $colinfos->{$source_alias} ||= $rsrc->columns_info )->{$colname} |
748 | || |
749 | $self->throw_exception( |
750 | "No such column '$colname' on source " . $rsrc->source_name |
751 | ); |
752 | }, |
d28bb90d |
753 | -result_source => $rsrc, |
52416317 |
754 | -source_alias => $source_alias, |
81bf295c |
755 | -fq_colname => $col eq $colname ? "$source_alias.$col" : $col, |
756 | -colname => $colname, |
d28bb90d |
757 | }; |
81bf295c |
758 | |
759 | $return{"$source_alias.$colname"} = $return{$col} if $col eq $colname; |
d28bb90d |
760 | } |
761 | |
762 | return \%return; |
763 | } |
764 | |
289ac713 |
765 | # The DBIC relationship chaining implementation is pretty simple - every |
766 | # new related_relationship is pushed onto the {from} stack, and the {select} |
767 | # window simply slides further in. This means that when we count somewhere |
768 | # in the middle, we got to make sure that everything in the join chain is an |
769 | # actual inner join, otherwise the count will come back with unpredictable |
770 | # results (a resultset may be generated with _some_ rows regardless of if |
771 | # the relation which the $rs currently selects has rows or not). E.g. |
772 | # $artist_rs->cds->count - normally generates: |
773 | # SELECT COUNT( * ) FROM artist me LEFT JOIN cd cds ON cds.artist = me.artistid |
774 | # which actually returns the number of artists * (number of cds || 1) |
775 | # |
776 | # So what we do here is crawl {from}, determine if the current alias is at |
777 | # the top of the stack, and if not - make sure the chain is inner-joined down |
778 | # to the root. |
779 | # |
31a8aaaf |
780 | sub _inner_join_to_node { |
289ac713 |
781 | my ($self, $from, $alias) = @_; |
782 | |
783 | # subqueries and other oddness are naturally not supported |
784 | return $from if ( |
785 | ref $from ne 'ARRAY' |
786 | || |
787 | @$from <= 1 |
788 | || |
789 | ref $from->[0] ne 'HASH' |
790 | || |
791 | ! $from->[0]{-alias} |
792 | || |
7eb76996 |
793 | $from->[0]{-alias} eq $alias # this last bit means $alias is the head of $from - nothing to do |
289ac713 |
794 | ); |
795 | |
796 | # find the current $alias in the $from structure |
797 | my $switch_branch; |
798 | JOINSCAN: |
799 | for my $j (@{$from}[1 .. $#$from]) { |
800 | if ($j->[0]{-alias} eq $alias) { |
801 | $switch_branch = $j->[0]{-join_path}; |
802 | last JOINSCAN; |
803 | } |
804 | } |
805 | |
7eb76996 |
806 | # something else went quite wrong |
289ac713 |
807 | return $from unless $switch_branch; |
808 | |
809 | # So it looks like we will have to switch some stuff around. |
810 | # local() is useless here as we will be leaving the scope |
811 | # anyway, and deep cloning is just too fucking expensive |
8273e845 |
812 | # So replace the first hashref in the node arrayref manually |
289ac713 |
813 | my @new_from = ($from->[0]); |
faeb2407 |
814 | my $sw_idx = { map { (values %$_), 1 } @$switch_branch }; #there's one k/v per join-path |
289ac713 |
815 | |
816 | for my $j (@{$from}[1 .. $#$from]) { |
817 | my $jalias = $j->[0]{-alias}; |
818 | |
819 | if ($sw_idx->{$jalias}) { |
820 | my %attrs = %{$j->[0]}; |
821 | delete $attrs{-join_type}; |
822 | push @new_from, [ |
823 | \%attrs, |
824 | @{$j}[ 1 .. $#$j ], |
825 | ]; |
826 | } |
827 | else { |
828 | push @new_from, $j; |
829 | } |
830 | } |
831 | |
832 | return \@new_from; |
833 | } |
834 | |
bac358c9 |
835 | sub _extract_order_criteria { |
1a736efb |
836 | my ($self, $order_by, $sql_maker) = @_; |
c0748280 |
837 | |
1a736efb |
838 | my $parser = sub { |
e6977bbb |
839 | my ($sql_maker, $order_by, $orig_quote_chars) = @_; |
c0748280 |
840 | |
1a736efb |
841 | return scalar $sql_maker->_order_by_chunks ($order_by) |
842 | unless wantarray; |
c0748280 |
843 | |
e6977bbb |
844 | my ($lq, $rq, $sep) = map { quotemeta($_) } ( |
845 | ($orig_quote_chars ? @$orig_quote_chars : $sql_maker->_quote_chars), |
846 | $sql_maker->name_sep |
847 | ); |
848 | |
1a736efb |
849 | my @chunks; |
bac358c9 |
850 | for ($sql_maker->_order_by_chunks ($order_by) ) { |
e6977bbb |
851 | my $chunk = ref $_ ? [ @$_ ] : [ $_ ]; |
cb3e87f5 |
852 | ($chunk->[0]) = $sql_maker->_split_order_chunk($chunk->[0]); |
e6977bbb |
853 | |
854 | # order criteria may have come back pre-quoted (literals and whatnot) |
855 | # this is fragile, but the best we can currently do |
856 | $chunk->[0] =~ s/^ $lq (.+?) $rq $sep $lq (.+?) $rq $/"$1.$2"/xe |
857 | or $chunk->[0] =~ s/^ $lq (.+) $rq $/$1/x; |
858 | |
1a736efb |
859 | push @chunks, $chunk; |
bac6c4fb |
860 | } |
1a736efb |
861 | |
862 | return @chunks; |
863 | }; |
864 | |
865 | if ($sql_maker) { |
866 | return $parser->($sql_maker, $order_by); |
bac6c4fb |
867 | } |
868 | else { |
1a736efb |
869 | $sql_maker = $self->sql_maker; |
e6977bbb |
870 | |
871 | # pass these in to deal with literals coming from |
872 | # the user or the deep guts of prefetch |
873 | my $orig_quote_chars = [$sql_maker->_quote_chars]; |
874 | |
1a736efb |
875 | local $sql_maker->{quote_char}; |
e6977bbb |
876 | return $parser->($sql_maker, $order_by, $orig_quote_chars); |
bac6c4fb |
877 | } |
bac6c4fb |
878 | } |
879 | |
7cec4356 |
880 | sub _order_by_is_stable { |
5f11e54f |
881 | my ($self, $ident, $order_by, $where) = @_; |
c0748280 |
882 | |
eb58c082 |
883 | my @cols = ( |
5f11e54f |
884 | (map { $_->[0] } $self->_extract_order_criteria($order_by)), |
885 | $where ? @{$self->_extract_fixed_condition_columns($where)} :(), |
eb58c082 |
886 | ) or return undef; |
887 | |
888 | my $colinfo = $self->_resolve_column_info($ident, \@cols); |
889 | |
890 | return keys %$colinfo |
891 | ? $self->_columns_comprise_identifying_set( $colinfo, \@cols ) |
892 | : undef |
893 | ; |
894 | } |
c0748280 |
895 | |
eb58c082 |
896 | sub _columns_comprise_identifying_set { |
897 | my ($self, $colinfo, $columns) = @_; |
7cec4356 |
898 | |
899 | my $cols_per_src; |
eb58c082 |
900 | $cols_per_src -> {$_->{-source_alias}} -> {$_->{-colname}} = $_ |
901 | for grep { defined $_ } @{$colinfo}{@$columns}; |
7cec4356 |
902 | |
903 | for (values %$cols_per_src) { |
904 | my $src = (values %$_)[0]->{-result_source}; |
905 | return 1 if $src->_identifying_column_set($_); |
c0748280 |
906 | } |
907 | |
7cec4356 |
908 | return undef; |
909 | } |
910 | |
0e81e691 |
911 | # this is almost identical to the above, except it accepts only |
912 | # a single rsrc, and will succeed only if the first portion of the order |
913 | # by is stable. |
914 | # returns that portion as a colinfo hashref on success |
915 | sub _main_source_order_by_portion_is_stable { |
916 | my ($self, $main_rsrc, $order_by, $where) = @_; |
917 | |
918 | die "Huh... I expect a blessed result_source..." |
919 | if ref($main_rsrc) eq 'ARRAY'; |
920 | |
921 | my @ord_cols = map |
922 | { $_->[0] } |
923 | ( $self->_extract_order_criteria($order_by) ) |
924 | ; |
925 | return unless @ord_cols; |
926 | |
318e3d94 |
927 | my $colinfos = $self->_resolve_column_info($main_rsrc); |
928 | |
0e81e691 |
929 | for (0 .. $#ord_cols) { |
930 | if ( |
931 | ! $colinfos->{$ord_cols[$_]} |
932 | or |
933 | $colinfos->{$ord_cols[$_]}{-result_source} != $main_rsrc |
934 | ) { |
935 | $#ord_cols = $_ - 1; |
936 | last; |
937 | } |
938 | } |
939 | |
940 | # we just truncated it above |
941 | return unless @ord_cols; |
942 | |
0e81e691 |
943 | my $order_portion_ci = { map { |
944 | $colinfos->{$_}{-colname} => $colinfos->{$_}, |
945 | $colinfos->{$_}{-fq_colname} => $colinfos->{$_}, |
946 | } @ord_cols }; |
947 | |
318e3d94 |
948 | # since all we check here are the start of the order_by belonging to the |
949 | # top level $rsrc, a present identifying set will mean that the resultset |
950 | # is ordered by its leftmost table in a stable manner |
951 | # |
952 | # RV of _identifying_column_set contains unqualified names only |
953 | my $unqualified_idset = $main_rsrc->_identifying_column_set({ |
954 | ( $where ? %{ |
955 | $self->_resolve_column_info( |
956 | $main_rsrc, $self->_extract_fixed_condition_columns($where) |
957 | ) |
958 | } : () ), |
959 | %$order_portion_ci |
960 | }) or return; |
961 | |
962 | my $ret_info; |
963 | my %unqualified_idcols_from_order = map { |
964 | $order_portion_ci->{$_} ? ( $_ => $order_portion_ci->{$_} ) : () |
965 | } @$unqualified_idset; |
966 | |
967 | # extra optimization - cut the order_by at the end of the identifying set |
968 | # (just in case the user was stupid and overlooked the obvious) |
969 | for my $i (0 .. $#ord_cols) { |
970 | my $col = $ord_cols[$i]; |
971 | my $unqualified_colname = $order_portion_ci->{$col}{-colname}; |
972 | $ret_info->{$col} = { %{$order_portion_ci->{$col}}, -idx_in_order_subset => $i }; |
973 | delete $unqualified_idcols_from_order{$ret_info->{$col}{-colname}}; |
974 | |
975 | # we didn't reach the end of the identifying portion yet |
976 | return $ret_info unless keys %unqualified_idcols_from_order; |
977 | } |
0e81e691 |
978 | |
318e3d94 |
979 | die 'How did we get here...'; |
0e81e691 |
980 | } |
981 | |
4a0eed52 |
982 | # returns an arrayref of column names which *definitely* have some |
5f11e54f |
983 | # sort of non-nullable equality requested in the given condition |
984 | # specification. This is used to figure out if a resultset is |
985 | # constrained to a column which is part of a unique constraint, |
986 | # which in turn allows us to better predict how ordering will behave |
987 | # etc. |
988 | # |
989 | # this is a rudimentary, incomplete, and error-prone extractor |
990 | # however this is OK - it is conservative, and if we can not find |
991 | # something that is in fact there - the stack will recover gracefully |
992 | # Also - DQ and the mst it rode in on will save us all RSN!!! |
993 | sub _extract_fixed_condition_columns { |
e1861c2c |
994 | my ($self, $where) = @_; |
5f11e54f |
995 | |
996 | return unless ref $where eq 'HASH'; |
997 | |
998 | my @cols; |
999 | for my $lhs (keys %$where) { |
1000 | if ($lhs =~ /^\-and$/i) { |
1001 | push @cols, ref $where->{$lhs} eq 'ARRAY' |
e1861c2c |
1002 | ? ( map { @{ $self->_extract_fixed_condition_columns($_) } } @{$where->{$lhs}} ) |
1003 | : @{ $self->_extract_fixed_condition_columns($where->{$lhs}) } |
5f11e54f |
1004 | ; |
1005 | } |
1006 | elsif ($lhs !~ /^\-/) { |
1007 | my $val = $where->{$lhs}; |
1008 | |
1009 | push @cols, $lhs if (defined $val and ( |
1010 | ! ref $val |
1011 | or |
1012 | (ref $val eq 'HASH' and keys %$val == 1 and defined $val->{'='}) |
1013 | )); |
1014 | } |
1015 | } |
e1861c2c |
1016 | return \@cols; |
c0748280 |
1017 | } |
bac6c4fb |
1018 | |
d28bb90d |
1019 | 1; |