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Changes In Branch pattern-compare-optimization Excluding Merge-Ins
This is equivalent to a diff from d2d30914 to a1e2b6ce
2016-12-01
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19:38 | Avoid clearing the EP_FromJoin flag from terms in ON clauses when flattening sub-selects. Possible fix for [2df0107b]. (Closed-Leaf check-in: 8bed4cd5 user: dan tags: left-join-fix) | |
18:57 | Performance improvement for GLOB and LIKE matching for patterns with two or more multi-character wildcards ("*" or "%"). (check-in: 2df0ebf9 user: drh tags: trunk) | |
18:49 | Faster version of patternCompare() that uses new return values rather than an extra parameter to communicate wildcard information back up to parent searches. (Closed-Leaf check-in: a1e2b6ce user: drh tags: pattern-compare-optimization) | |
17:34 | Modify the patternCompare() function (used for GLOB, LIKE) to better handle patterns containing multiple wildcard characters ("*", "%"). (check-in: c5e5614d user: dan tags: pattern-compare-optimization) | |
2016-11-30
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16:54 | Add the remember(V,PTR) extension function which copies an SQL value into an application variable. (check-in: d2d30914 user: drh tags: trunk) | |
14:47 | Fix then handling of the (oversized) integer literal -0x8000000000000000. (check-in: 3816bb41 user: drh tags: trunk) | |
2016-08-09
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21:08 | Prototype for the remember(V,PTR) extension function. (Closed-Leaf check-in: f0942c36 user: drh tags: rememberFunc) | |
Changes to src/func.c.
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594 595 596 597 598 599 600 | ** case. Thus 'a' LIKE 'A' would be true. */ static const struct compareInfo likeInfoNorm = { '%', '_', 0, 1 }; /* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator ** is case sensitive causing 'a' LIKE 'A' to be false */ static const struct compareInfo likeInfoAlt = { '%', '_', 0, 0 }; /* | > > > > > > > | | < > > > > | 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 | ** case. Thus 'a' LIKE 'A' would be true. */ static const struct compareInfo likeInfoNorm = { '%', '_', 0, 1 }; /* If SQLITE_CASE_SENSITIVE_LIKE is defined, then the LIKE operator ** is case sensitive causing 'a' LIKE 'A' to be false */ static const struct compareInfo likeInfoAlt = { '%', '_', 0, 0 }; /* ** Possible error returns from patternMatch() */ #define SQLITE_MATCH 0 #define SQLITE_NOMATCH 1 #define SQLITE_NOWILDCARDMATCH 2 /* ** Compare two UTF-8 strings for equality where the first string is ** a GLOB or LIKE expression. Return values: ** ** SQLITE_MATCH: Match ** SQLITE_NOMATCH: No match ** SQLITE_NOWILDCARDMATCH: No match in spite of having * or % wildcards. ** ** Globbing rules: ** ** '*' Matches any sequence of zero or more characters. ** ** '?' Matches exactly one character. ** |
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647 648 649 650 651 652 653 | while( (c = Utf8Read(zPattern))!=0 ){ if( c==matchAll ){ /* Match "*" */ /* Skip over multiple "*" characters in the pattern. If there ** are also "?" characters, skip those as well, but consume a ** single character of the input string for each "?" skipped */ while( (c=Utf8Read(zPattern)) == matchAll || c == matchOne ){ if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){ | | | | | | > | | > | > > | > | | | | 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 | while( (c = Utf8Read(zPattern))!=0 ){ if( c==matchAll ){ /* Match "*" */ /* Skip over multiple "*" characters in the pattern. If there ** are also "?" characters, skip those as well, but consume a ** single character of the input string for each "?" skipped */ while( (c=Utf8Read(zPattern)) == matchAll || c == matchOne ){ if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){ return SQLITE_NOWILDCARDMATCH; } } if( c==0 ){ return SQLITE_MATCH; /* "*" at the end of the pattern matches */ }else if( c==matchOther ){ if( pInfo->matchSet==0 ){ c = sqlite3Utf8Read(&zPattern); if( c==0 ) return SQLITE_NOWILDCARDMATCH; }else{ /* "[...]" immediately follows the "*". We have to do a slow ** recursive search in this case, but it is an unusual case. */ assert( matchOther<0x80 ); /* '[' is a single-byte character */ while( *zString ){ int bMatch = patternCompare(&zPattern[-1],zString,pInfo,matchOther); if( bMatch!=SQLITE_NOMATCH ) return bMatch; SQLITE_SKIP_UTF8(zString); } return SQLITE_NOWILDCARDMATCH; } } /* At this point variable c contains the first character of the ** pattern string past the "*". Search in the input string for the ** first matching character and recursively continue the match from ** that point. ** ** For a case-insensitive search, set variable cx to be the same as ** c but in the other case and search the input string for either ** c or cx. */ if( c<=0x80 ){ u32 cx; int bMatch; if( noCase ){ cx = sqlite3Toupper(c); c = sqlite3Tolower(c); }else{ cx = c; } while( (c2 = *(zString++))!=0 ){ if( c2!=c && c2!=cx ) continue; bMatch = patternCompare(zPattern,zString,pInfo,matchOther); if( bMatch!=SQLITE_NOMATCH ) return bMatch; } }else{ int bMatch; while( (c2 = Utf8Read(zString))!=0 ){ if( c2!=c ) continue; bMatch = patternCompare(zPattern,zString,pInfo,matchOther); if( bMatch!=SQLITE_NOMATCH ) return bMatch; } } return SQLITE_NOWILDCARDMATCH; } if( c==matchOther ){ if( pInfo->matchSet==0 ){ c = sqlite3Utf8Read(&zPattern); if( c==0 ) return SQLITE_NOMATCH; zEscaped = zPattern; }else{ u32 prior_c = 0; int seen = 0; int invert = 0; c = sqlite3Utf8Read(&zString); if( c==0 ) return SQLITE_NOMATCH; c2 = sqlite3Utf8Read(&zPattern); if( c2=='^' ){ invert = 1; c2 = sqlite3Utf8Read(&zPattern); } if( c2==']' ){ if( c==']' ) seen = 1; |
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731 732 733 734 735 736 737 | seen = 1; } prior_c = c2; } c2 = sqlite3Utf8Read(&zPattern); } if( c2==0 || (seen ^ invert)==0 ){ | | | | | > | | > | | 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 | seen = 1; } prior_c = c2; } c2 = sqlite3Utf8Read(&zPattern); } if( c2==0 || (seen ^ invert)==0 ){ return SQLITE_NOMATCH; } continue; } } c2 = Utf8Read(zString); if( c==c2 ) continue; if( noCase && sqlite3Tolower(c)==sqlite3Tolower(c2) && c<0x80 && c2<0x80 ){ continue; } if( c==matchOne && zPattern!=zEscaped && c2!=0 ) continue; return SQLITE_NOMATCH; } return *zString==0 ? SQLITE_MATCH : SQLITE_NOMATCH; } /* ** The sqlite3_strglob() interface. Return 0 on a match (like strcmp()) and ** non-zero if there is no match. */ int sqlite3_strglob(const char *zGlobPattern, const char *zString){ return patternCompare((u8*)zGlobPattern, (u8*)zString, &globInfo, '['); } /* ** The sqlite3_strlike() interface. Return 0 on a match and non-zero for ** a miss - like strcmp(). */ int sqlite3_strlike(const char *zPattern, const char *zStr, unsigned int esc){ return patternCompare((u8*)zPattern, (u8*)zStr, &likeInfoNorm, esc); } /* ** Count the number of times that the LIKE operator (or GLOB which is ** just a variation of LIKE) gets called. This is used for testing ** only. */ |
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839 840 841 842 843 844 845 | }else{ escape = pInfo->matchSet; } if( zA && zB ){ #ifdef SQLITE_TEST sqlite3_like_count++; #endif | | | 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 | }else{ escape = pInfo->matchSet; } if( zA && zB ){ #ifdef SQLITE_TEST sqlite3_like_count++; #endif sqlite3_result_int(context, patternCompare(zB, zA, pInfo, escape)==SQLITE_MATCH); } } /* ** Implementation of the NULLIF(x,y) function. The result is the first ** argument if the arguments are different. The result is NULL if the ** arguments are equal to each other. |
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