forked from mongodb/mongo
-
Notifications
You must be signed in to change notification settings - Fork 0
/
queryutil.cpp
1562 lines (1458 loc) · 61.6 KB
/
queryutil.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// @file queryutil.cpp
/* Copyright 2009 10gen Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "pch.h"
#include "btree.h"
#include "matcher.h"
#include "pdfile.h"
#include "queryoptimizer.h"
#include "../util/unittest.h"
#include "dbmessage.h"
#include "indexkey.h"
#include "../util/mongoutils/str.h"
namespace mongo {
extern BSONObj staticNull;
extern BSONObj staticUndefined;
/** returns a string that when used as a matcher, would match a super set of regex()
returns "" for complex regular expressions
used to optimize queries in some simple regex cases that start with '^'
if purePrefix != NULL, sets it to whether the regex can be converted to a range query
*/
string simpleRegex(const char* regex, const char* flags, bool* purePrefix) {
string r = "";
if (purePrefix) *purePrefix = false;
bool multilineOK;
if ( regex[0] == '\\' && regex[1] == 'A') {
multilineOK = true;
regex += 2;
}
else if (regex[0] == '^') {
multilineOK = false;
regex += 1;
}
else {
return r;
}
bool extended = false;
while (*flags) {
switch (*(flags++)) {
case 'm': // multiline
if (multilineOK)
continue;
else
return r;
case 'x': // extended
extended = true;
break;
default:
return r; // cant use index
}
}
stringstream ss;
while(*regex) {
char c = *(regex++);
if ( c == '*' || c == '?' ) {
// These are the only two symbols that make the last char optional
r = ss.str();
r = r.substr( 0 , r.size() - 1 );
return r; //breaking here fails with /^a?/
}
else if (c == '|') {
// whole match so far is optional. Nothing we can do here.
return string();
}
else if (c == '\\') {
c = *(regex++);
if (c == 'Q'){
// \Q...\E quotes everything inside
while (*regex) {
c = (*regex++);
if (c == '\\' && (*regex == 'E')){
regex++; //skip the 'E'
break; // go back to start of outer loop
}
else {
ss << c; // character should match itself
}
}
}
else if ((c >= 'A' && c <= 'Z') ||
(c >= 'a' && c <= 'z') ||
(c >= '0' && c <= '0') ||
(c == '\0')) {
// don't know what to do with these
r = ss.str();
break;
}
else {
// slash followed by non-alphanumeric represents the following char
ss << c;
}
}
else if (strchr("^$.[()+{", c)) {
// list of "metacharacters" from man pcrepattern
r = ss.str();
break;
}
else if (extended && c == '#') {
// comment
r = ss.str();
break;
}
else if (extended && isspace(c)) {
continue;
}
else {
// self-matching char
ss << c;
}
}
if ( r.empty() && *regex == 0 ) {
r = ss.str();
if (purePrefix) *purePrefix = !r.empty();
}
return r;
}
inline string simpleRegex(const BSONElement& e) {
switch(e.type()) {
case RegEx:
return simpleRegex(e.regex(), e.regexFlags());
case Object: {
BSONObj o = e.embeddedObject();
return simpleRegex(o["$regex"].valuestrsafe(), o["$options"].valuestrsafe());
}
default: assert(false); return ""; //return squashes compiler warning
}
}
string simpleRegexEnd( string regex ) {
++regex[ regex.length() - 1 ];
return regex;
}
FieldRange::FieldRange( const BSONElement &e, bool singleKey, bool isNot, bool optimize )
: _singleKey( singleKey ) {
int op = e.getGtLtOp();
// NOTE with $not, we could potentially form a complementary set of intervals.
if ( !isNot && !e.eoo() && e.type() != RegEx && op == BSONObj::opIN ) {
set<BSONElement,element_lt> vals;
vector<FieldRange> regexes;
uassert( 12580 , "invalid query" , e.isABSONObj() );
BSONObjIterator i( e.embeddedObject() );
while( i.more() ) {
BSONElement ie = i.next();
uassert( 15881, "$elemMatch not allowed within $in",
ie.type() != Object ||
ie.embeddedObject().firstElement().getGtLtOp() != BSONObj::opELEM_MATCH );
if ( ie.type() == RegEx ) {
regexes.push_back( FieldRange( ie, singleKey, false, optimize ) );
}
else {
// A document array may be indexed by its first element, by undefined
// if it is empty, or as a full array if it is embedded within another
// array.
vals.insert( ie );
if ( ie.type() == Array ) {
BSONElement temp = ie.embeddedObject().firstElement();
if ( temp.eoo() ) {
temp = staticUndefined.firstElement();
}
vals.insert( temp );
}
}
}
for( set<BSONElement,element_lt>::const_iterator i = vals.begin(); i != vals.end(); ++i )
_intervals.push_back( FieldInterval(*i) );
for( vector<FieldRange>::const_iterator i = regexes.begin(); i != regexes.end(); ++i )
*this |= *i;
return;
}
// A document array may be indexed by its first element, by undefined
// if it is empty, or as a full array if it is embedded within another
// array.
if ( e.type() == Array && op == BSONObj::Equality ) {
_intervals.push_back( FieldInterval(e) );
BSONElement temp = e.embeddedObject().firstElement();
if ( temp.eoo() ) {
temp = staticUndefined.firstElement();
}
if ( temp < e ) {
_intervals.insert( _intervals.begin() , temp );
}
else {
_intervals.push_back( FieldInterval(temp) );
}
return;
}
_intervals.push_back( FieldInterval() );
FieldInterval &initial = _intervals[ 0 ];
BSONElement &lower = initial._lower._bound;
bool &lowerInclusive = initial._lower._inclusive;
BSONElement &upper = initial._upper._bound;
bool &upperInclusive = initial._upper._inclusive;
lower = minKey.firstElement();
lowerInclusive = true;
upper = maxKey.firstElement();
upperInclusive = true;
if ( e.eoo() )
return;
bool existsSpec = false;
if ( op == BSONObj::opEXISTS ) {
existsSpec = e.trueValue();
}
if ( e.type() == RegEx
|| (e.type() == Object && !e.embeddedObject()["$regex"].eoo())
) {
uassert( 13454, "invalid regular expression operator", op == BSONObj::Equality || op == BSONObj::opREGEX );
if ( !isNot ) { // no optimization for negated regex - we could consider creating 2 intervals comprising all nonmatching prefixes
const string r = simpleRegex(e);
if ( r.size() ) {
lower = addObj( BSON( "" << r ) ).firstElement();
upper = addObj( BSON( "" << simpleRegexEnd( r ) ) ).firstElement();
upperInclusive = false;
}
else {
BSONObjBuilder b1(32), b2(32);
b1.appendMinForType( "" , String );
lower = addObj( b1.obj() ).firstElement();
b2.appendMaxForType( "" , String );
upper = addObj( b2.obj() ).firstElement();
upperInclusive = false; //MaxForType String is an empty Object
}
// regex matches self - regex type > string type
if (e.type() == RegEx) {
BSONElement re = addObj( BSON( "" << e ) ).firstElement();
_intervals.push_back( FieldInterval(re) );
}
else {
BSONObj orig = e.embeddedObject();
BSONObjBuilder b;
b.appendRegex("", orig["$regex"].valuestrsafe(), orig["$options"].valuestrsafe());
BSONElement re = addObj( b.obj() ).firstElement();
_intervals.push_back( FieldInterval(re) );
}
}
return;
}
if ( isNot ) {
switch( op ) {
case BSONObj::Equality:
return;
// op = BSONObj::NE;
// break;
case BSONObj::opALL:
case BSONObj::opMOD: // NOTE for mod and type, we could consider having 1-2 intervals comprising the complementary types (multiple intervals already possible with $in)
case BSONObj::opTYPE:
// no bound calculation
return;
case BSONObj::NE:
op = BSONObj::Equality;
break;
case BSONObj::LT:
op = BSONObj::GTE;
break;
case BSONObj::LTE:
op = BSONObj::GT;
break;
case BSONObj::GT:
op = BSONObj::LTE;
break;
case BSONObj::GTE:
op = BSONObj::LT;
break;
case BSONObj::opEXISTS:
existsSpec = !existsSpec;
break;
default: // otherwise doesn't matter
break;
}
}
switch( op ) {
case BSONObj::Equality:
lower = upper = e;
break;
case BSONObj::NE: {
// this will invalidate the upper/lower references above
_intervals.push_back( FieldInterval() );
// optimize doesn't make sense for negative ranges
_intervals[ 0 ]._upper._bound = e;
_intervals[ 0 ]._upper._inclusive = false;
_intervals[ 1 ]._lower._bound = e;
_intervals[ 1 ]._lower._inclusive = false;
_intervals[ 1 ]._upper._bound = maxKey.firstElement();
_intervals[ 1 ]._upper._inclusive = true;
optimize = false; // don't run optimize code below
break;
}
case BSONObj::LT:
upperInclusive = false;
case BSONObj::LTE:
upper = e;
break;
case BSONObj::GT:
lowerInclusive = false;
case BSONObj::GTE:
lower = e;
break;
case BSONObj::opALL: {
uassert( 10370 , "$all requires array", e.type() == Array );
BSONObjIterator i( e.embeddedObject() );
bool bound = false;
while ( i.more() ) {
BSONElement x = i.next();
if ( x.type() == Object && x.embeddedObject().firstElement().getGtLtOp() == BSONObj::opELEM_MATCH ) {
// taken care of elsewhere
}
else if ( x.type() != RegEx ) {
lower = upper = x;
bound = true;
break;
}
}
if ( !bound ) { // if no good non regex bound found, try regex bounds
BSONObjIterator i( e.embeddedObject() );
while( i.more() ) {
BSONElement x = i.next();
if ( x.type() != RegEx )
continue;
string simple = simpleRegex( x.regex(), x.regexFlags() );
if ( !simple.empty() ) {
lower = addObj( BSON( "" << simple ) ).firstElement();
upper = addObj( BSON( "" << simpleRegexEnd( simple ) ) ).firstElement();
break;
}
}
}
break;
}
case BSONObj::opMOD: {
{
BSONObjBuilder b;
b.appendMinForType( "" , NumberDouble );
lower = addObj( b.obj() ).firstElement();
}
{
BSONObjBuilder b;
b.appendMaxForType( "" , NumberDouble );
upper = addObj( b.obj() ).firstElement();
}
break;
}
case BSONObj::opTYPE: {
BSONType t = (BSONType)e.numberInt();
{
BSONObjBuilder b;
b.appendMinForType( "" , t );
lower = addObj( b.obj() ).firstElement();
}
{
BSONObjBuilder b;
b.appendMaxForType( "" , t );
upper = addObj( b.obj() ).firstElement();
}
break;
}
case BSONObj::opREGEX:
case BSONObj::opOPTIONS:
// do nothing
break;
case BSONObj::opELEM_MATCH: {
log() << "warning: shouldn't get here?" << endl;
break;
}
case BSONObj::opNEAR:
case BSONObj::opWITHIN:
_special = "2d";
break;
case BSONObj::opEXISTS: {
if ( !existsSpec ) {
lower = upper = staticNull.firstElement();
}
optimize = false;
break;
}
default:
break;
}
if ( optimize ) {
if ( lower.type() != MinKey && upper.type() == MaxKey && lower.isSimpleType() ) { // TODO: get rid of isSimpleType
BSONObjBuilder b;
b.appendMaxForType( lower.fieldName() , lower.type() );
upper = addObj( b.obj() ).firstElement();
}
else if ( lower.type() == MinKey && upper.type() != MaxKey && upper.isSimpleType() ) { // TODO: get rid of isSimpleType
if( upper.type() == Date )
lowerInclusive = false;
BSONObjBuilder b;
b.appendMinForType( upper.fieldName() , upper.type() );
lower = addObj( b.obj() ).firstElement();
}
}
}
void FieldRange::finishOperation( const vector<FieldInterval> &newIntervals, const FieldRange &other ) {
_intervals = newIntervals;
for( vector<BSONObj>::const_iterator i = other._objData.begin(); i != other._objData.end(); ++i )
_objData.push_back( *i );
if ( _special.size() == 0 && other._special.size() )
_special = other._special;
}
// as called, these functions find the max/min of a bound in the
// opposite direction, so inclusive bounds are considered less
// superlative
FieldBound maxFieldBound( const FieldBound &a, const FieldBound &b ) {
int cmp = a._bound.woCompare( b._bound, false );
if ( ( cmp == 0 && !b._inclusive ) || cmp < 0 )
return b;
return a;
}
FieldBound minFieldBound( const FieldBound &a, const FieldBound &b ) {
int cmp = a._bound.woCompare( b._bound, false );
if ( ( cmp == 0 && !b._inclusive ) || cmp > 0 )
return b;
return a;
}
bool fieldIntervalOverlap( const FieldInterval &one, const FieldInterval &two, FieldInterval &result ) {
result._lower = maxFieldBound( one._lower, two._lower );
result._upper = minFieldBound( one._upper, two._upper );
return result.strictValid();
}
const FieldRange &FieldRange::operator&=( const FieldRange &other ) {
if ( !_singleKey && nontrivial() ) {
if ( other <= *this ) {
*this = other;
}
return *this;
}
vector<FieldInterval> newIntervals;
vector<FieldInterval>::const_iterator i = _intervals.begin();
vector<FieldInterval>::const_iterator j = other._intervals.begin();
while( i != _intervals.end() && j != other._intervals.end() ) {
FieldInterval overlap;
if ( fieldIntervalOverlap( *i, *j, overlap ) ) {
newIntervals.push_back( overlap );
}
if ( i->_upper == minFieldBound( i->_upper, j->_upper ) ) {
++i;
}
else {
++j;
}
}
finishOperation( newIntervals, other );
return *this;
}
void handleInterval( const FieldInterval &lower, FieldBound &low, FieldBound &high, vector<FieldInterval> &newIntervals ) {
if ( low._bound.eoo() ) {
low = lower._lower; high = lower._upper;
}
else {
int cmp = high._bound.woCompare( lower._lower._bound, false );
if ( ( cmp < 0 ) || ( cmp == 0 && !high._inclusive && !lower._lower._inclusive ) ) {
FieldInterval tmp;
tmp._lower = low;
tmp._upper = high;
newIntervals.push_back( tmp );
low = lower._lower; high = lower._upper;
}
else {
high = lower._upper;
}
}
}
const FieldRange &FieldRange::operator|=( const FieldRange &other ) {
vector<FieldInterval> newIntervals;
FieldBound low;
FieldBound high;
vector<FieldInterval>::const_iterator i = _intervals.begin();
vector<FieldInterval>::const_iterator j = other._intervals.begin();
while( i != _intervals.end() && j != other._intervals.end() ) {
int cmp = i->_lower._bound.woCompare( j->_lower._bound, false );
if ( ( cmp == 0 && i->_lower._inclusive ) || cmp < 0 ) {
handleInterval( *i, low, high, newIntervals );
++i;
}
else {
handleInterval( *j, low, high, newIntervals );
++j;
}
}
while( i != _intervals.end() ) {
handleInterval( *i, low, high, newIntervals );
++i;
}
while( j != other._intervals.end() ) {
handleInterval( *j, low, high, newIntervals );
++j;
}
FieldInterval tmp;
tmp._lower = low;
tmp._upper = high;
newIntervals.push_back( tmp );
finishOperation( newIntervals, other );
return *this;
}
const FieldRange &FieldRange::operator-=( const FieldRange &other ) {
vector<FieldInterval> newIntervals;
vector<FieldInterval>::iterator i = _intervals.begin();
vector<FieldInterval>::const_iterator j = other._intervals.begin();
while( i != _intervals.end() && j != other._intervals.end() ) {
int cmp = i->_lower._bound.woCompare( j->_lower._bound, false );
if ( cmp < 0 ||
( cmp == 0 && i->_lower._inclusive && !j->_lower._inclusive ) ) {
int cmp2 = i->_upper._bound.woCompare( j->_lower._bound, false );
if ( cmp2 < 0 ) {
newIntervals.push_back( *i );
++i;
}
else if ( cmp2 == 0 ) {
newIntervals.push_back( *i );
if ( newIntervals.back()._upper._inclusive && j->_lower._inclusive ) {
newIntervals.back()._upper._inclusive = false;
}
++i;
}
else {
newIntervals.push_back( *i );
newIntervals.back()._upper = j->_lower;
newIntervals.back()._upper.flipInclusive();
int cmp3 = i->_upper._bound.woCompare( j->_upper._bound, false );
if ( cmp3 < 0 ||
( cmp3 == 0 && ( !i->_upper._inclusive || j->_upper._inclusive ) ) ) {
++i;
}
else {
i->_lower = j->_upper;
i->_lower.flipInclusive();
++j;
}
}
}
else {
int cmp2 = i->_lower._bound.woCompare( j->_upper._bound, false );
if ( cmp2 > 0 ||
( cmp2 == 0 && ( !i->_lower._inclusive || !j->_upper._inclusive ) ) ) {
++j;
}
else {
int cmp3 = i->_upper._bound.woCompare( j->_upper._bound, false );
if ( cmp3 < 0 ||
( cmp3 == 0 && ( !i->_upper._inclusive || j->_upper._inclusive ) ) ) {
++i;
}
else {
i->_lower = j->_upper;
i->_lower.flipInclusive();
++j;
}
}
}
}
while( i != _intervals.end() ) {
newIntervals.push_back( *i );
++i;
}
finishOperation( newIntervals, other );
return *this;
}
// TODO write a proper implementation that doesn't do a full copy
bool FieldRange::operator<=( const FieldRange &other ) const {
FieldRange temp = *this;
temp -= other;
return temp.empty();
}
void FieldRange::setExclusiveBounds() {
for( vector<FieldInterval>::iterator i = _intervals.begin(); i != _intervals.end(); ++i ) {
i->_lower._inclusive = false;
i->_upper._inclusive = false;
}
}
void FieldRange::reverse( FieldRange &ret ) const {
assert( _special.empty() );
ret._intervals.clear();
ret._objData = _objData;
for( vector<FieldInterval>::const_reverse_iterator i = _intervals.rbegin(); i != _intervals.rend(); ++i ) {
FieldInterval fi;
fi._lower = i->_upper;
fi._upper = i->_lower;
ret._intervals.push_back( fi );
}
}
BSONObj FieldRange::addObj( const BSONObj &o ) {
_objData.push_back( o );
return o;
}
string FieldInterval::toString() const {
StringBuilder buf;
buf << ( _lower._inclusive ? "[" : "(" );
buf << _lower._bound;
buf << " , ";
buf << _upper._bound;
buf << ( _upper._inclusive ? "]" : ")" );
return buf.str();
}
string FieldRange::toString() const {
StringBuilder buf;
buf << "(FieldRange special: " << _special << " singleKey: " << _special << " intervals: ";
for( vector<FieldInterval>::const_iterator i = _intervals.begin(); i != _intervals.end(); ++i ) {
buf << i->toString();
}
buf << ")";
return buf.str();
}
string FieldRangeSet::getSpecial() const {
string s = "";
for ( map<string,FieldRange>::const_iterator i=_ranges.begin(); i!=_ranges.end(); i++ ) {
if ( i->second.getSpecial().size() == 0 )
continue;
uassert( 13033 , "can't have 2 special fields" , s.size() == 0 );
s = i->second.getSpecial();
}
return s;
}
/**
* Btree scanning for a multidimentional key range will yield a
* multidimensional box. The idea here is that if an 'other'
* multidimensional box contains the current box we don't have to scan
* the current box. If the 'other' box contains the current box in
* all dimensions but one, we can safely subtract the values of 'other'
* along that one dimension from the values for the current box on the
* same dimension. In other situations, subtracting the 'other'
* box from the current box yields a result that is not a box (but
* rather can be expressed as a union of boxes). We don't support
* such splitting currently in calculating index ranges. Note that
* where I have said 'box' above, I actually mean sets of boxes because
* a field range can consist of multiple intervals.
*/
const FieldRangeSet &FieldRangeSet::operator-=( const FieldRangeSet &other ) {
int nUnincluded = 0;
string unincludedKey;
map<string,FieldRange>::iterator i = _ranges.begin();
map<string,FieldRange>::const_iterator j = other._ranges.begin();
while( nUnincluded < 2 && i != _ranges.end() && j != other._ranges.end() ) {
int cmp = i->first.compare( j->first );
if ( cmp == 0 ) {
if ( i->second <= j->second ) {
// nothing
}
else {
++nUnincluded;
unincludedKey = i->first;
}
++i;
++j;
}
else if ( cmp < 0 ) {
++i;
}
else {
// other has a bound we don't, nothing can be done
return *this;
}
}
if ( j != other._ranges.end() ) {
// other has a bound we don't, nothing can be done
return *this;
}
if ( nUnincluded > 1 ) {
return *this;
}
if ( nUnincluded == 0 ) {
makeEmpty();
return *this;
}
// nUnincluded == 1
range( unincludedKey.c_str() ) -= other.range( unincludedKey.c_str() );
appendQueries( other );
return *this;
}
const FieldRangeSet &FieldRangeSet::operator&=( const FieldRangeSet &other ) {
map<string,FieldRange>::iterator i = _ranges.begin();
map<string,FieldRange>::const_iterator j = other._ranges.begin();
while( i != _ranges.end() && j != other._ranges.end() ) {
int cmp = i->first.compare( j->first );
if ( cmp == 0 ) {
// Same field name, so find range intersection.
i->second &= j->second;
++i;
++j;
}
else if ( cmp < 0 ) {
// Field present in *this.
++i;
}
else {
// Field not present in *this, so add it.
range( j->first.c_str() ) = j->second;
++j;
}
}
while( j != other._ranges.end() ) {
// Field not present in *this, add it.
range( j->first.c_str() ) = j->second;
++j;
}
appendQueries( other );
return *this;
}
void FieldRangeSet::appendQueries( const FieldRangeSet &other ) {
for( vector<BSONObj>::const_iterator i = other._queries.begin(); i != other._queries.end(); ++i ) {
_queries.push_back( *i );
}
}
void FieldRangeSet::makeEmpty() {
for( map<string,FieldRange>::iterator i = _ranges.begin(); i != _ranges.end(); ++i ) {
i->second.makeEmpty();
}
}
void FieldRangeSet::processOpElement( const char *fieldName, const BSONElement &f, bool isNot, bool optimize ) {
BSONElement g = f;
int op2 = g.getGtLtOp();
if ( op2 == BSONObj::opALL ) {
BSONElement h = g;
uassert( 13050 , "$all requires array", h.type() == Array );
BSONObjIterator i( h.embeddedObject() );
if( i.more() ) {
BSONElement x = i.next();
if ( x.type() == Object && x.embeddedObject().firstElement().getGtLtOp() == BSONObj::opELEM_MATCH ) {
g = x.embeddedObject().firstElement();
op2 = g.getGtLtOp();
}
}
}
if ( op2 == BSONObj::opELEM_MATCH ) {
BSONObjIterator k( g.embeddedObjectUserCheck() );
while ( k.more() ) {
BSONElement h = k.next();
StringBuilder buf(32);
buf << fieldName << "." << h.fieldName();
string fullname = buf.str();
int op3 = getGtLtOp( h );
if ( op3 == BSONObj::Equality ) {
range( fullname.c_str() ) &= FieldRange( h , _singleKey , isNot , optimize );
}
else {
BSONObjIterator l( h.embeddedObject() );
while ( l.more() ) {
range( fullname.c_str() ) &= FieldRange( l.next() , _singleKey , isNot , optimize );
}
}
}
}
else {
range( fieldName ) &= FieldRange( f , _singleKey , isNot , optimize );
}
}
void FieldRangeSet::processQueryField( const BSONElement &e, bool optimize ) {
if ( e.fieldName()[ 0 ] == '$' ) {
if ( strcmp( e.fieldName(), "$and" ) == 0 ) {
uassert( 14816 , "$and expression must be a nonempty array" , e.type() == Array && e.embeddedObject().nFields() > 0 );
BSONObjIterator i( e.embeddedObject() );
while( i.more() ) {
BSONElement e = i.next();
uassert( 14817 , "$and elements must be objects" , e.type() == Object );
BSONObjIterator j( e.embeddedObject() );
while( j.more() ) {
processQueryField( j.next(), optimize );
}
}
}
if ( strcmp( e.fieldName(), "$where" ) == 0 ) {
return;
}
if ( strcmp( e.fieldName(), "$or" ) == 0 ) {
return;
}
if ( strcmp( e.fieldName(), "$nor" ) == 0 ) {
return;
}
}
bool equality = ( getGtLtOp( e ) == BSONObj::Equality );
if ( equality && e.type() == Object ) {
equality = ( strcmp( e.embeddedObject().firstElementFieldName(), "$not" ) != 0 );
}
if ( equality || ( e.type() == Object && !e.embeddedObject()[ "$regex" ].eoo() ) ) {
range( e.fieldName() ) &= FieldRange( e , _singleKey , false , optimize );
}
if ( !equality ) {
BSONObjIterator j( e.embeddedObject() );
while( j.more() ) {
BSONElement f = j.next();
if ( strcmp( f.fieldName(), "$not" ) == 0 ) {
switch( f.type() ) {
case Object: {
BSONObjIterator k( f.embeddedObject() );
while( k.more() ) {
BSONElement g = k.next();
uassert( 13034, "invalid use of $not", g.getGtLtOp() != BSONObj::Equality );
processOpElement( e.fieldName(), g, true, optimize );
}
break;
}
case RegEx:
processOpElement( e.fieldName(), f, true, optimize );
break;
default:
uassert( 13041, "invalid use of $not", false );
}
}
else {
processOpElement( e.fieldName(), f, false, optimize );
}
}
}
}
FieldRangeSet::FieldRangeSet( const char *ns, const BSONObj &query, bool singleKey, bool optimize )
: _ns( ns ), _queries( 1, query.getOwned() ), _singleKey( singleKey ) {
BSONObjIterator i( _queries[ 0 ] );
while( i.more() ) {
processQueryField( i.next(), optimize );
}
}
FieldRangeVector::FieldRangeVector( const FieldRangeSet &frs, const IndexSpec &indexSpec, int direction )
:_indexSpec( indexSpec ), _direction( direction >= 0 ? 1 : -1 ) {
_queries = frs._queries;
BSONObjIterator i( _indexSpec.keyPattern );
set< string > baseObjectNontrivialPrefixes;
while( i.more() ) {
BSONElement e = i.next();
const FieldRange *range = &frs.range( e.fieldName() );
if ( !frs.singleKey() ) {
string prefix = str::before( e.fieldName(), '.' );
if ( baseObjectNontrivialPrefixes.count( prefix ) > 0 ) {
// A field with the same parent field has already been
// constrainted, and with a multikey index we cannot
// constrain this field.
range = &frs.trivialRange();
} else {
if ( range->nontrivial() ) {
baseObjectNontrivialPrefixes.insert( prefix );
}
}
}
int number = (int) e.number(); // returns 0.0 if not numeric
bool forward = ( ( number >= 0 ? 1 : -1 ) * ( direction >= 0 ? 1 : -1 ) > 0 );
if ( forward ) {
_ranges.push_back( *range );
}
else {
_ranges.push_back( FieldRange( BSONObj().firstElement(), frs.singleKey(), false, true ) );
range->reverse( _ranges.back() );
}
assert( !_ranges.back().empty() );
}
uassert( 13385, "combinatorial limit of $in partitioning of result set exceeded", size() < 1000000 );
}
BSONObj FieldRangeVector::startKey() const {
BSONObjBuilder b;
for( vector<FieldRange>::const_iterator i = _ranges.begin(); i != _ranges.end(); ++i ) {
const FieldInterval &fi = i->intervals().front();
b.appendAs( fi._lower._bound, "" );
}
return b.obj();
}
BSONObj FieldRangeVector::endKey() const {
BSONObjBuilder b;
for( vector<FieldRange>::const_iterator i = _ranges.begin(); i != _ranges.end(); ++i ) {
const FieldInterval &fi = i->intervals().back();
b.appendAs( fi._upper._bound, "" );
}
return b.obj();
}
BSONObj FieldRangeVector::obj() const {
BSONObjBuilder b;
BSONObjIterator k( _indexSpec.keyPattern );
for( int i = 0; i < (int)_ranges.size(); ++i ) {
BSONArrayBuilder a( b.subarrayStart( k.next().fieldName() ) );
for( vector<FieldInterval>::const_iterator j = _ranges[ i ].intervals().begin();
j != _ranges[ i ].intervals().end(); ++j ) {
a << BSONArray( BSON_ARRAY( j->_lower._bound << j->_upper._bound ).clientReadable() );
}
a.done();
}
return b.obj();
}
FieldRange *FieldRangeSet::__singleKeyTrivialRange = 0;
FieldRange *FieldRangeSet::__multiKeyTrivialRange = 0;
const FieldRange &FieldRangeSet::trivialRange() const {
FieldRange *&ret = _singleKey ? __singleKeyTrivialRange : __multiKeyTrivialRange;
if ( ret == 0 ) {
ret = new FieldRange( BSONObj().firstElement(), _singleKey, false, true );
}
return *ret;
}
BSONObj FieldRangeSet::simplifiedQuery( const BSONObj &_fields ) const {
BSONObj fields = _fields;
if ( fields.isEmpty() ) {
BSONObjBuilder b;
for( map<string,FieldRange>::const_iterator i = _ranges.begin(); i != _ranges.end(); ++i ) {
b.append( i->first, 1 );
}
fields = b.obj();
}
BSONObjBuilder b;
BSONObjIterator i( fields );
while( i.more() ) {
BSONElement e = i.next();
const char *name = e.fieldName();
const FieldRange &eRange = range( name );
assert( !eRange.empty() );
if ( eRange.equality() )
b.appendAs( eRange.min(), name );
else if ( eRange.nontrivial() ) {
BSONObj o;
BSONObjBuilder c;
if ( eRange.min().type() != MinKey )
c.appendAs( eRange.min(), eRange.minInclusive() ? "$gte" : "$gt" );
if ( eRange.max().type() != MaxKey )
c.appendAs( eRange.max(), eRange.maxInclusive() ? "$lte" : "$lt" );
o = c.obj();
b.append( name, o );
}
}
return b.obj();
}
QueryPattern FieldRangeSet::pattern( const BSONObj &sort ) const {
QueryPattern qp;
for( map<string,FieldRange>::const_iterator i = _ranges.begin(); i != _ranges.end(); ++i ) {
assert( !i->second.empty() );
if ( i->second.equality() ) {
qp._fieldTypes[ i->first ] = QueryPattern::Equality;
}