About

A set of SQLite 3 extensions that allow perform a approximate string searching.

Compiling

In order to compile this extensions You need an gcc or clang (just install Xcode 4.2) and sqlite library installed (comes bundled with OS X but installed from MacPorts or Homebrew is ok).

To compile an extension using a command-line:

clang -bundle -fPIC -Isqlite3 -o <desired extension name>.sqlext <filename>.c

For example, to compile a extension that uses Levenshtein distance:

clang -bundle -fPIC -Isqlite3 -o levenshtein.sqlext levenshtein.c

Usage

Loading extension

In order to use extension you need to load it. You can do this by calling:

.load <path to extension file>

For example, if you want to load a Soundex extension, you need to call:

.load soundex.sqlext

Note that you should start sqlite interactive shell in the same directory that contains soundex.sqlext file. Otherwise you need to specify full path.

Using functions in SQL query

Basically these extensions just define a number of functions that could be used in SQL query.

For example, if you want to fetch all items that have a name similar to orange via Soundex algorithm, you should use this query:

SELECT * FROM items WHERE SOUNDEX(name) == SOUNDEX('orange')

If you want to fetch all peoples with name that has a Levenshtein dispense less than 3 with word "John" you should use this query:

SELECT * FROM peoples WHERE LEVENSHTEIN(name,'John',3)