80 lines
2.2 KiB
Plaintext
Executable File
80 lines
2.2 KiB
Plaintext
Executable File
This directory contains a module that implements the "Metaphone" code as
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a PostgreSQL user-defined function. The Metaphone system is a method of
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matching similar sounding names (or any words) to the same code.
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Metaphone was invented by Lawrence Philips as an improvement to the popular
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name-hashing routine, Soundex.
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This metaphone code is from Michael Kuhn, and is detailed at
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http://aspell.sourceforge.net/metaphone/metaphone-kuhn.txt
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Code for this (including this help file!) was liberally borrowed from
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the soundex() module for PostgreSQL.
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There are two functions:
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metaphone(text) : returns hash of a name
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metaphone(text,int) : returns hash (maximum length of int) of name
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---
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To install it, first configure the main source tree, then run make;
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make install in this directory. Finally, load the function definition
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with psql:
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psql -f PREFIX/share/contrib/metaphone.sql
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The following are some usage examples:
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SELECT text_metaphone('hello world!');
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SELECT text_metaphone('hello world!', 4);
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CREATE TABLE s (nm text)\g
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insert into s values ('john')\g
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insert into s values ('joan')\g
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insert into s values ('wobbly')\g
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select * from s
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where text_metaphone(nm) = text_metaphone('john')\g
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select nm from s a, s b
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where text_metaphone(a.nm) = text_metaphone(b.nm)
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and a.oid <> b.oid\g
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CREATE FUNCTION text_mp_eq(text, text) RETURNS bool AS
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'select text_metaphone($1) = text_metaphone($2)'
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LANGUAGE 'sql'\g
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CREATE FUNCTION text_mp_lt(text,text) RETURNS bool AS
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'select text_metaphone($1) < text_metaphone($2)'
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LANGUAGE 'sql'\g
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CREATE FUNCTION text_mp_gt(text,text) RETURNS bool AS
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'select text_metaphone($1) > text_metaphone($2)'
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LANGUAGE 'sql';
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CREATE FUNCTION text_mp_le(text,text) RETURNS bool AS
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'select text_metaphone($1) <= text_metaphone($2)'
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LANGUAGE 'sql';
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CREATE FUNCTION text_mp_ge(text,text) RETURNS bool AS
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'select text_metaphone($1) >= text_metaphone($2)'
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LANGUAGE 'sql';
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CREATE FUNCTION text_mp_ne(text,text) RETURNS bool AS
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'select text_metaphone($1) <> text_metaphone($2)'
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LANGUAGE 'sql';
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DROP OPERATOR #= (text,text)\g
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CREATE OPERATOR #= (leftarg=text, rightarg=text, procedure=text_mp_eq,
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commutator=text_mp_eq)\g
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SELECT *
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FROM s
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WHERE text_mp_eq(nm,'pillsbury')\g
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SELECT *
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from s
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where s.nm #= 'pillsbury';
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