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Get rid of VARATT_SIZE and VARATT_DATA, which were simply redundant with VARSIZE and VARDATA, and as a consequence almost no code was using the longer names. Rename the length fields of struct varlena and various derived structures to catch anyplace that was accessing them directly; and clean up various places so caught. In itself this patch doesn't change any behavior at all, but it is necessary infrastructure if we hope to play any games with the representation of varlena headers. Greg Stark and Tom Lane |
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dmetaphone.c | ||
fuzzystrmatch.c | ||
fuzzystrmatch.h | ||
fuzzystrmatch.sql.in | ||
Makefile | ||
README.fuzzystrmatch | ||
README.soundex | ||
uninstall_fuzzystrmatch.sql |
NOTE: Modified August 07, 2001 by Joe Conway. Updated for accuracy after combining soundex code into the fuzzystrmatch contrib --------------------------------------------------------------------- The Soundex system is a method of matching similar sounding names (or any words) to the same code. It was initially used by the United States Census in 1880, 1900, and 1910, but it has little use beyond English names (or the English pronunciation of names), and it is not a linguistic tool. When comparing two soundex values to determine similarity, the difference function reports how close the match is on a scale from zero to four, with zero being no match and four being an exact match. The following are some usage examples: SELECT soundex('hello world!'); SELECT soundex('Anne'), soundex('Ann'), difference('Anne', 'Ann'); SELECT soundex('Anne'), soundex('Andrew'), difference('Anne', 'Andrew'); SELECT soundex('Anne'), soundex('Margaret'), difference('Anne', 'Margaret'); CREATE TABLE s (nm text); INSERT INTO s VALUES ('john'); INSERT INTO s VALUES ('joan'); INSERT INTO s VALUES ('wobbly'); INSERT INTO s VALUES ('jack'); SELECT * FROM s WHERE soundex(nm) = soundex('john'); SELECT a.nm, b.nm FROM s a, s b WHERE soundex(a.nm) = soundex(b.nm) AND a.oid <> b.oid; CREATE FUNCTION text_sx_eq(text, text) RETURNS boolean AS 'select soundex($1) = soundex($2)' LANGUAGE SQL; CREATE FUNCTION text_sx_lt(text, text) RETURNS boolean AS 'select soundex($1) < soundex($2)' LANGUAGE SQL; CREATE FUNCTION text_sx_gt(text, text) RETURNS boolean AS 'select soundex($1) > soundex($2)' LANGUAGE SQL; CREATE FUNCTION text_sx_le(text, text) RETURNS boolean AS 'select soundex($1) <= soundex($2)' LANGUAGE SQL; CREATE FUNCTION text_sx_ge(text, text) RETURNS boolean AS 'select soundex($1) >= soundex($2)' LANGUAGE SQL; CREATE FUNCTION text_sx_ne(text, text) RETURNS boolean AS 'select soundex($1) <> soundex($2)' LANGUAGE SQL; DROP OPERATOR #= (text, text); CREATE OPERATOR #= (leftarg=text, rightarg=text, procedure=text_sx_eq, commutator = #=); SELECT * FROM s WHERE text_sx_eq(nm, 'john'); SELECT * FROM s WHERE s.nm #= 'john'; SELECT * FROM s WHERE difference(s.nm, 'john') > 2;