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