diff --git a/contrib/README b/contrib/README index 2e071e2f83..5823520c0f 100644 --- a/contrib/README +++ b/contrib/README @@ -55,6 +55,10 @@ fulltextindex - Full text indexing using triggers by Maarten Boekhold +fuzzystrmatch - + Levenshtein and Metaphone fuzzy string matching + by Joe Conway + intarray - Index support for arrays of int4, using GiST by Teodor Sigaev and Oleg Bartunov diff --git a/contrib/fuzzystrmatch/Makefile b/contrib/fuzzystrmatch/Makefile new file mode 100644 index 0000000000..5f75b4ac68 --- /dev/null +++ b/contrib/fuzzystrmatch/Makefile @@ -0,0 +1,41 @@ +subdir = contrib/fuzzystrmatch +top_builddir = ../.. +include $(top_builddir)/src/Makefile.global + +# override libdir to install shlib in contrib not main directory +libdir := $(libdir)/contrib + +# shared library parameters +NAME= fuzzystrmatch +SO_MAJOR_VERSION= 0 +SO_MINOR_VERSION= 1 + +override CPPFLAGS := -I$(srcdir)/src/include $(CPPFLAGS) + +OBJS= fuzzystrmatch.o + +all: all-lib $(NAME).sql + +# Shared library stuff +include $(top_srcdir)/src/Makefile.shlib + + +$(NAME).sql: $(NAME).sql.in + sed -e 's:MODULE_PATHNAME:$(libdir)/$(shlib):g' < $< > $@ + +install: all installdirs install-lib + +installdirs: + $(mkinstalldirs) $(DESTDIR)$(libdir) + +uninstall: uninstall-lib + +clean distclean maintainer-clean: clean-lib + rm -f $(OBJS) $(NAME).sql + +depend dep: + $(CC) -MM $(CFLAGS) *.c >depend + +ifeq (depend,$(wildcard depend)) +include depend +endif diff --git a/contrib/fuzzystrmatch/README.fuzzystrmatch b/contrib/fuzzystrmatch/README.fuzzystrmatch new file mode 100644 index 0000000000..9109ea7e06 --- /dev/null +++ b/contrib/fuzzystrmatch/README.fuzzystrmatch @@ -0,0 +1,121 @@ +/* + * fuzzystrmatch.c + * + * Functions for "fuzzy" comparison of strings + * + * Copyright (c) Joseph Conway , 2001; + * + * levenshtein() + * ------------- + * Written based on a description of the algorithm by Michael Gilleland + * found at http://www.merriampark.com/ld.htm + * Also looked at levenshtein.c in the PHP 4.0.6 distribution for + * inspiration. + * + * metaphone() + * ----------- + * Modified for PostgreSQL by Joe Conway. + * Based on CPAN's "Text-Metaphone-1.96" by Michael G Schwern + * Code slightly modified for use as PostgreSQL function (palloc, elog, etc). + * Metaphone was originally created by Lawrence Philips and presented in article + * in "Computer Language" December 1990 issue. + * + * Permission to use, copy, modify, and distribute this software and its + * documentation for any purpose, without fee, and without a written agreement + * is hereby granted, provided that the above copyright notice and this + * paragraph and the following two paragraphs appear in all copies. + * + * IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR + * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING + * LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS + * DOCUMENTATION, EVEN IF THE AUTHOR OR DISTRIBUTORS HAVE BEEN ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + * THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS + * ON AN "AS IS" BASIS, AND THE AUTHOR AND DISTRIBUTORS HAS NO OBLIGATIONS TO + * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. + * + */ + + +Version 0.1 (3 August, 2001): + Functions to calculate the degree to which two strings match in a "fuzzy" way + Tested under Linux (Red Hat 6.2 and 7.0) and PostgreSQL 7.2devel + +Release Notes: + + Version 0.1 + - initial release + +Installation: + Place these files in a directory called 'fuzzystrmatch' under 'contrib' in the PostgreSQL source tree. Then run: + + make + make install + + You can use fuzzystrmatch.sql to create the functions in your database of choice, e.g. + + psql -U postgres template1 < fuzzystrmatch.sql + + installs following functions into database template1: + + levenshtein() - calculates the levenshtein distance between two strings + metaphone() - calculates the metaphone code of an input string + +Documentation +================================================================== +Name + +levenshtein -- calculates the levenshtein distance between two strings + +Synopsis + +levenshtein(text source, text target) + +Inputs + + source + any text string, 255 characters max, NOT NULL + + target + any text string, 255 characters max, NOT NULL + +Outputs + + Returns int + +Example usage + + select levenshtein('GUMBO','GAMBOL'); + +================================================================== +Name + +metaphone -- calculates the metaphone code of an input string + +Synopsis + +metaphone(text source, int max_output_length) + +Inputs + + source + any text string, 255 characters max, NOT NULL + + max_output_length + maximum length of the output metaphone code; if longer, the output + is truncated to this length + +Outputs + + Returns text + +Example usage + + select metaphone('GUMBO',4); + +================================================================== +-- Joe Conway + diff --git a/contrib/fuzzystrmatch/fuzzystrmatch.c b/contrib/fuzzystrmatch/fuzzystrmatch.c new file mode 100644 index 0000000000..80e9e69cfa --- /dev/null +++ b/contrib/fuzzystrmatch/fuzzystrmatch.c @@ -0,0 +1,631 @@ +/* + * fuzzystrmatch.c + * + * Functions for "fuzzy" comparison of strings + * + * Copyright (c) Joseph Conway , 2001; + * + * levenshtein() + * ------------- + * Written based on a description of the algorithm by Michael Gilleland + * found at http://www.merriampark.com/ld.htm + * Also looked at levenshtein.c in the PHP 4.0.6 distribution for + * inspiration. + * + * metaphone() + * ----------- + * Modified for PostgreSQL by Joe Conway. + * Based on CPAN's "Text-Metaphone-1.96" by Michael G Schwern + * Code slightly modified for use as PostgreSQL function (palloc, elog, etc). + * Metaphone was originally created by Lawrence Philips and presented in article + * in "Computer Language" December 1990 issue. + * + * Permission to use, copy, modify, and distribute this software and its + * documentation for any purpose, without fee, and without a written agreement + * is hereby granted, provided that the above copyright notice and this + * paragraph and the following two paragraphs appear in all copies. + * + * IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR + * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING + * LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS + * DOCUMENTATION, EVEN IF THE AUTHOR OR DISTRIBUTORS HAVE BEEN ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + * THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS + * ON AN "AS IS" BASIS, AND THE AUTHOR AND DISTRIBUTORS HAS NO OBLIGATIONS TO + * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. + * + */ + +#include "fuzzystrmatch.h" + +/* + * Calculates Levenshtein Distance between two strings. + * Uses simplest and fastest cost model only, i.e. assumes a cost of 1 for + * each deletion, substitution, or insertion. + */ +PG_FUNCTION_INFO_V1(levenshtein); +Datum +levenshtein(PG_FUNCTION_ARGS) +{ + char *str_s; + char *str_s0; + char *str_t; + int cols = 0; + int rows = 0; + int *u_cells; + int *l_cells; + int *tmp; + int i; + int j; + + /* + * Fetch the arguments. + * str_s is referred to as the "source" + * cols = length of source + 1 to allow for the initialization column + * str_t is referred to as the "target", rows = length of target + 1 + * rows = length of target + 1 to allow for the initialization row + */ + str_s = DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(PG_GETARG_TEXT_P(0)))); + str_t = DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(PG_GETARG_TEXT_P(1)))); + + cols = strlen(str_s) + 1; + rows = strlen(str_t) + 1; + + /* + * Restrict the length of the strings being compared to something reasonable + * because we will have to perform rows * cols calcualtions. If longer strings need to be + * compared, increase MAX_LEVENSHTEIN_STRLEN to suit (but within your tolerance for + * speed and memory usage). + */ + if ((cols > MAX_LEVENSHTEIN_STRLEN + 1) || (rows > MAX_LEVENSHTEIN_STRLEN + 1)) + elog(ERROR, "levenshtein: Arguments may not exceed %d characters in length", MAX_LEVENSHTEIN_STRLEN); + + /* + * If either rows or cols is 0, the answer is the other value. + * This makes sense since it would take that many insertions + * the build a matching string + */ + + if (cols == 0) + PG_RETURN_INT32(rows); + + if (rows == 0) + PG_RETURN_INT32(cols); + + /* + * Allocate two vectors of integers. One will be used for the "upper" row, + * the other for the "lower" row. Initialize the "upper" row to 0..cols + */ + u_cells = palloc(sizeof(int) * cols); + for (i = 0; i < cols; i++) + u_cells[i] = i; + + l_cells = palloc(sizeof(int) * cols); + + /* + * Use str_s0 to "rewind" the pointer to str_s in the nested for loop below + */ + str_s0 = str_s; + + /* + * Loop throught the rows, starting at row 1. Row 0 is used for the initial + * "upper" row. + */ + for (j = 1; j < rows; j++) + { + /* + * We'll always start with col 1, + * and initialize lower row col 0 to j + */ + l_cells[0] = j; + + for (i = 1; i < cols; i++) + { + int c = 0; + int c1 = 0; + int c2 = 0; + int c3 = 0; + + /* + * The "cost" value is 0 if the character at the current col position + * in the source string, matches the character at the current row position + * in the target string; cost is 1 otherwise. + */ + c = ((CHAREQ(str_s, str_t)) ? 0 : 1); + + /* + * c1 is upper right cell plus 1 + */ + c1 = u_cells[i] + 1; + + /* + * c2 is lower left cell plus 1 + */ + c2 = l_cells[i - 1] + 1; + + /* + * c3 is cell diagonally above to the left plus "cost" + */ + c3 = u_cells[i - 1] + c; + + /* + * The lower right cell is set to the minimum + * of c1, c2, c3 + */ + l_cells[i] = (c1 < c2 ? c1 : c2) < c3 ? (c1 < c2 ? c1 : c2) : c3; + + /* + * Increment the pointer to str_s + */ + NextChar(str_s); + } + + /* + * Lower row now becomes the upper row, and the upper row + * gets reused as the new lower row. + */ + tmp = u_cells; + u_cells = l_cells; + l_cells = tmp; + + /* + * Increment the pointer to str_t + */ + NextChar(str_t); + + /* + * Rewind the pointer to str_s + */ + str_s = str_s0; + } + + /* + * Because the final value (at position row, col) was swapped from + * the lower row to the upper row, that's where we'll find it. + */ + PG_RETURN_INT32(u_cells[cols - 1]); +} + +/* + * Calculates the metaphone of an input string. + * Returns number of characters requested + * (suggested value is 4) + */ +PG_FUNCTION_INFO_V1(metaphone); +Datum +metaphone(PG_FUNCTION_ARGS) +{ + int reqlen; + char *str_i; + size_t str_i_len; + char *metaph; + text *result_text; + int retval; + + str_i = DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(PG_GETARG_TEXT_P(0)))); + str_i_len = strlen(str_i); + + if (str_i_len > MAX_METAPHONE_STRLEN) + elog(ERROR, "metaphone: Input string must not exceed %d characters", MAX_METAPHONE_STRLEN); + if (!(str_i_len > 0)) + elog(ERROR, "metaphone: Input string length must be > 0"); + + reqlen = PG_GETARG_INT32(1); + if (reqlen > MAX_METAPHONE_STRLEN) + elog(ERROR, "metaphone: Requested Metaphone output length must not exceed %d characters", MAX_METAPHONE_STRLEN); + if (!(reqlen > 0)) + elog(ERROR, "metaphone: Requested Metaphone output length must be > 0"); + + metaph = palloc(reqlen); + memset(metaph, '\0', reqlen); + + retval = _metaphone(str_i, reqlen, &metaph); + if (retval == META_SUCCESS) + { + result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(metaph))); + PG_RETURN_TEXT_P(result_text); + } + else + { + elog(ERROR, "metaphone: failure"); + + /* + * Keep the compiler quiet + */ + PG_RETURN_NULL(); + } +} + + +/* + * Original code by Michael G Schwern starts here. + * Code slightly modified for use as PostgreSQL + * function (palloc, etc). Original includes + * are rolled into fuzzystrmatch.h + *------------------------------------------------------------------*/ + +/* I suppose I could have been using a character pointer instead of + * accesssing the array directly... */ + +/* Look at the next letter in the word */ +#define Next_Letter (toupper(word[w_idx+1])) +/* Look at the current letter in the word */ +#define Curr_Letter (toupper(word[w_idx])) +/* Go N letters back. */ +#define Look_Back_Letter(n) (w_idx >= n ? toupper(word[w_idx-n]) : '\0') +/* Previous letter. I dunno, should this return null on failure? */ +#define Prev_Letter (Look_Back_Letter(1)) +/* Look two letters down. It makes sure you don't walk off the string. */ +#define After_Next_Letter (Next_Letter != '\0' ? toupper(word[w_idx+2]) \ + : '\0') +#define Look_Ahead_Letter(n) (toupper(Lookahead(word+w_idx, n))) + + +/* Allows us to safely look ahead an arbitrary # of letters */ +/* I probably could have just used strlen... */ +char Lookahead(char * word, int how_far) { + char letter_ahead = '\0'; /* null by default */ + int idx; + for(idx = 0; word[idx] != '\0' && idx < how_far; idx++); + /* Edge forward in the string... */ + + letter_ahead = word[idx]; /* idx will be either == to how_far or + * at the end of the string + */ + return letter_ahead; +} + + +/* phonize one letter */ +#define Phonize(c) {(*phoned_word)[p_idx++] = c;} +/* Slap a null character on the end of the phoned word */ +#define End_Phoned_Word {(*phoned_word)[p_idx] = '\0';} +/* How long is the phoned word? */ +#define Phone_Len (p_idx) + +/* Note is a letter is a 'break' in the word */ +#define Isbreak(c) (!isalpha(c)) + + +int _metaphone ( + /* IN */ + char * word, + int max_phonemes, + /* OUT */ + char ** phoned_word +) { + int w_idx = 0; /* point in the phonization we're at. */ + int p_idx = 0; /* end of the phoned phrase */ + + /*-- Parameter checks --*/ + + /* + * Shouldn't be necessary, but left these here anyway + * jec Aug 3, 2001 + */ + + /* Negative phoneme length is meaningless */ + if (!(max_phonemes > 0)) + elog(ERROR, "metaphone: Requested output length must be > 0"); + + /* Empty/null string is meaningless */ + if ((word == NULL) || !(strlen(word) > 0)) + elog(ERROR, "metaphone: Input string length must be > 0"); + + /*-- Allocate memory for our phoned_phrase --*/ + if (max_phonemes == 0) { /* Assume largest possible */ + *phoned_word = palloc(sizeof(char) * strlen(word) + 1); + if (!*phoned_word) + return META_ERROR; + } else { + *phoned_word = palloc(sizeof(char) * max_phonemes + 1); + if (!*phoned_word) + return META_ERROR; + } + + /*-- The first phoneme has to be processed specially. --*/ + /* Find our first letter */ + for( ; !isalpha(Curr_Letter); w_idx++ ) { + /* On the off chance we were given nothing but crap... */ + if( Curr_Letter == '\0' ) { + End_Phoned_Word + return META_SUCCESS; /* For testing */ + } + } + + switch (Curr_Letter) { + /* AE becomes E */ + case 'A': + if( Next_Letter == 'E' ) { + Phonize('E'); + w_idx+=2; + } + /* Remember, preserve vowels at the beginning */ + else { + Phonize('A'); + w_idx++; + } + break; + /* [GKP]N becomes N */ + case 'G': + case 'K': + case 'P': + if( Next_Letter == 'N' ) { + Phonize('N'); + w_idx+=2; + } + break; + /* WH becomes H, + WR becomes R + W if followed by a vowel */ + case 'W': + if( Next_Letter == 'H' || + Next_Letter == 'R' ) + { + Phonize(Next_Letter); + w_idx+=2; + } + else if ( isvowel(Next_Letter) ) { + Phonize('W'); + w_idx+=2; + } + /* else ignore */ + break; + /* X becomes S */ + case 'X': + Phonize('S'); + w_idx++; + break; + /* Vowels are kept */ + /* We did A already + case 'A': + case 'a': + */ + case 'E': + case 'I': + case 'O': + case 'U': + Phonize(Curr_Letter); + w_idx++; + break; + default: + /* do nothing */ + break; + } + + + + /* On to the metaphoning */ + for(; Curr_Letter != '\0' && + (max_phonemes == 0 || Phone_Len < max_phonemes); + w_idx++) { + /* How many letters to skip because an eariler encoding handled + * multiple letters */ + unsigned short int skip_letter = 0; + + + /* THOUGHT: It would be nice if, rather than having things like... + * well, SCI. For SCI you encode the S, then have to remember + * to skip the C. So the phonome SCI invades both S and C. It would + * be better, IMHO, to skip the C from the S part of the encoding. + * Hell, I'm trying it. + */ + + /* Ignore non-alphas */ + if( !isalpha(Curr_Letter) ) + continue; + + /* Drop duplicates, except CC */ + if( Curr_Letter == Prev_Letter && + Curr_Letter != 'C' ) + continue; + + switch (Curr_Letter) { + /* B -> B unless in MB */ + case 'B': + if( Prev_Letter != 'M' ) + Phonize('B'); + break; + /* 'sh' if -CIA- or -CH, but not SCH, except SCHW. + * (SCHW is handled in S) + * S if -CI-, -CE- or -CY- + * dropped if -SCI-, SCE-, -SCY- (handed in S) + * else K + */ + case 'C': + if( MAKESOFT(Next_Letter) ) { /* C[IEY] */ + if( After_Next_Letter == 'A' && + Next_Letter == 'I' ) { /* CIA */ + Phonize(SH); + } + /* SC[IEY] */ + else if ( Prev_Letter == 'S' ) { + /* Dropped */ + } + else { + Phonize('S'); + } + } + else if ( Next_Letter == 'H' ) { +#ifndef USE_TRADITIONAL_METAPHONE + if( After_Next_Letter == 'R' || + Prev_Letter == 'S' ) { /* Christ, School */ + Phonize('K'); + } + else { + Phonize(SH); + } +#else + Phonize(SH); +#endif + skip_letter++; + } + else { + Phonize('K'); + } + break; + /* J if in -DGE-, -DGI- or -DGY- + * else T + */ + case 'D': + if( Next_Letter == 'G' && + MAKESOFT(After_Next_Letter) ) { + Phonize('J'); + skip_letter++; + } + else + Phonize('T'); + break; + /* F if in -GH and not B--GH, D--GH, -H--GH, -H---GH + * else dropped if -GNED, -GN, + * else dropped if -DGE-, -DGI- or -DGY- (handled in D) + * else J if in -GE-, -GI, -GY and not GG + * else K + */ + case 'G': + if( Next_Letter == 'H' ) { + if( !( NOGHTOF(Look_Back_Letter(3)) || + Look_Back_Letter(4) == 'H' ) ) { + Phonize('F'); + skip_letter++; + } + else { + /* silent */ + } + } + else if( Next_Letter == 'N' ) { + if( Isbreak(After_Next_Letter) || + ( After_Next_Letter == 'E' && + Look_Ahead_Letter(3) == 'D' ) ) { + /* dropped */ + } + else + Phonize('K'); + } + else if( MAKESOFT(Next_Letter) && + Prev_Letter != 'G' ) { + Phonize('J'); + } + else { + Phonize('K'); + } + break; + /* H if before a vowel and not after C,G,P,S,T */ + case 'H': + if( isvowel(Next_Letter) && + !AFFECTH(Prev_Letter) ) + Phonize('H'); + break; + /* dropped if after C + * else K + */ + case 'K': + if( Prev_Letter != 'C' ) + Phonize('K'); + break; + /* F if before H + * else P + */ + case 'P': + if( Next_Letter == 'H' ) { + Phonize('F'); + } + else { + Phonize('P'); + } + break; + /* K + */ + case 'Q': + Phonize('K'); + break; + /* 'sh' in -SH-, -SIO- or -SIA- or -SCHW- + * else S + */ + case 'S': + if( Next_Letter == 'I' && + ( After_Next_Letter == 'O' || + After_Next_Letter == 'A' ) ) { + Phonize(SH); + } + else if ( Next_Letter == 'H' ) { + Phonize(SH); + skip_letter++; + } +#ifndef USE_TRADITIONAL_METAPHONE + else if ( Next_Letter == 'C' && + Look_Ahead_Letter(2) == 'H' && + Look_Ahead_Letter(3) == 'W' ) { + Phonize(SH); + skip_letter += 2; + } +#endif + else { + Phonize('S'); + } + break; + /* 'sh' in -TIA- or -TIO- + * else 'th' before H + * else T + */ + case 'T': + if( Next_Letter == 'I' && + ( After_Next_Letter == 'O' || + After_Next_Letter == 'A' ) ) { + Phonize(SH); + } + else if ( Next_Letter == 'H' ) { + Phonize(TH); + skip_letter++; + } + else { + Phonize('T'); + } + break; + /* F */ + case 'V': + Phonize('F'); + break; + /* W before a vowel, else dropped */ + case 'W': + if( isvowel(Next_Letter) ) + Phonize('W'); + break; + /* KS */ + case 'X': + Phonize('K'); + Phonize('S'); + break; + /* Y if followed by a vowel */ + case 'Y': + if( isvowel(Next_Letter) ) + Phonize('Y'); + break; + /* S */ + case 'Z': + Phonize('S'); + break; + /* No transformation */ + case 'F': + case 'J': + case 'L': + case 'M': + case 'N': + case 'R': + Phonize(Curr_Letter); + break; + default: + /* nothing */ + break; + } /* END SWITCH */ + + w_idx += skip_letter; + } /* END FOR */ + + End_Phoned_Word; + + return(META_SUCCESS); +} /* END metaphone */ diff --git a/contrib/fuzzystrmatch/fuzzystrmatch.h b/contrib/fuzzystrmatch/fuzzystrmatch.h new file mode 100644 index 0000000000..5ed9c3746e --- /dev/null +++ b/contrib/fuzzystrmatch/fuzzystrmatch.h @@ -0,0 +1,161 @@ +/* + * fuzzystrmatch.h + * + * Functions for "fuzzy" comparison of strings + * + * Copyright (c) Joseph Conway , 2001; + * + * levenshtein() + * ------------- + * Written based on a description of the algorithm by Michael Gilleland + * found at http://www.merriampark.com/ld.htm + * Also looked at levenshtein.c in the PHP 4.0.6 distribution for + * inspiration. + * + * metaphone() + * ----------- + * Modified for PostgreSQL by Joe Conway. + * Based on CPAN's "Text-Metaphone-1.96" by Michael G Schwern + * Code slightly modified for use as PostgreSQL function (palloc, elog, etc). + * Metaphone was originally created by Lawrence Philips and presented in article + * in "Computer Language" December 1990 issue. + * + * Permission to use, copy, modify, and distribute this software and its + * documentation for any purpose, without fee, and without a written agreement + * is hereby granted, provided that the above copyright notice and this + * paragraph and the following two paragraphs appear in all copies. + * + * IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR + * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING + * LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS + * DOCUMENTATION, EVEN IF THE AUTHOR OR DISTRIBUTORS HAVE BEEN ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + * THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS + * ON AN "AS IS" BASIS, AND THE AUTHOR AND DISTRIBUTORS HAS NO OBLIGATIONS TO + * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. + * + */ + +#ifndef FUZZYSTRMATCH_H +#define FUZZYSTRMATCH_H + +#include +#include +#include + +#include "postgres.h" +#include "fmgr.h" +#include "utils/builtins.h" + + +#define MAX_LEVENSHTEIN_STRLEN 255 +#define MAX_METAPHONE_STRLEN 255 + +typedef struct dynmatrix +{ + int value; +} dynmat; + + +/* + * External declarations + */ +extern Datum levenshtein(PG_FUNCTION_ARGS); +extern Datum metaphone(PG_FUNCTION_ARGS); + +/* + * Internal declarations + */ + + + +#define STRLEN(p) strlen(p) +#define CHAREQ(p1, p2) (*(p1) == *(p2)) +#define NextChar(p) ((p)++) + + +/* + * Original code by Michael G Schwern starts here. + * Code slightly modified for use as PostgreSQL + * function (combined *.h into here). + *------------------------------------------------------------------*/ + +/************************************************************************** + metaphone -- Breaks english phrases down into their phonemes. + + Input + word -- An english word to be phonized + max_phonemes -- How many phonemes to calculate. If 0, then it + will phonize the entire phrase. + phoned_word -- The final phonized word. (We'll allocate the + memory.) + Output + error -- A simple error flag, returns TRUE or FALSE + + NOTES: ALL non-alpha characters are ignored, this includes whitespace, + although non-alpha characters will break up phonemes. +****************************************************************************/ + + +/************************************************************************** + my constants -- constants I like + + Probably redundant. + +***************************************************************************/ + +#define META_ERROR FALSE +#define META_SUCCESS TRUE +#define META_FAILURE FALSE + + +/* I add modifications to the traditional metaphone algorithm that you + might find in books. Define this if you want metaphone to behave + traditionally */ +#undef USE_TRADITIONAL_METAPHONE + +/* Special encodings */ +#define SH 'X' +#define TH '0' + +char Lookahead(char * word, int how_far); +int _metaphone ( + /* IN */ + char * word, + int max_phonemes, + /* OUT */ + char ** phoned_word +); + +/* Metachar.h ... little bits about characters for metaphone */ + + +/*-- Character encoding array & accessing macros --*/ +/* Stolen directly out of the book... */ +char _codes[26] = { + 1,16,4,16,9,2,4,16,9,2,0,2,2,2,1,4,0,2,4,4,1,0,0,0,8,0 +/* a b c d e f g h i j k l m n o p q r s t u v w x y z */ +}; + + +#define ENCODE(c) (isalpha(c) ? _codes[((toupper(c)) - 'A')] : 0) + +#define isvowel(c) (ENCODE(c) & 1) /* AEIOU */ + +/* These letters are passed through unchanged */ +#define NOCHANGE(c) (ENCODE(c) & 2) /* FJMNR */ + +/* These form dipthongs when preceding H */ +#define AFFECTH(c) (ENCODE(c) & 4) /* CGPST */ + +/* These make C and G soft */ +#define MAKESOFT(c) (ENCODE(c) & 8) /* EIY */ + +/* These prevent GH from becoming F */ +#define NOGHTOF(c) (ENCODE(c) & 16) /* BDH */ + + +#endif /* FUZZYSTRMATCH_H */ diff --git a/contrib/fuzzystrmatch/fuzzystrmatch.sql.in b/contrib/fuzzystrmatch/fuzzystrmatch.sql.in new file mode 100644 index 0000000000..4125b75d14 --- /dev/null +++ b/contrib/fuzzystrmatch/fuzzystrmatch.sql.in @@ -0,0 +1,5 @@ +CREATE FUNCTION levenshtein (text,text) RETURNS int + AS 'MODULE_PATHNAME','levenshtein' LANGUAGE 'c' with (iscachable, isstrict); + +CREATE FUNCTION metaphone (text,int) RETURNS text + AS 'MODULE_PATHNAME','metaphone' LANGUAGE 'c' with (iscachable, isstrict);