Use SOUNDEX() word by word on SQL Server

Question

Here is my problem. For example I have a table Products that contains a field, Name:

Products
ID | Name | ..
1  | "USB Key 10Go"
2  | "Intel computer"
3  | "12 inches laptop computer"
...

I'm currently implementing a simple search engine (SQL Server and ASP .NET, C#) for an iPhone web-app and I would like to use the SOUNDEX() SQL Server function.

The thing is, I can't directly use SOUNDEX on the Name field. (This would be irrelevant since there are several words in the name.) I would like to apply the SOUNDEX function to each word from the Name field, and then see if any of them matches the researched keyword.

If someone has any clue how to do this, that would be awesome.

Answer 1

Rather than use Soundex you might be better off computing the Levenshtein distance between the two strings. See the Wikipedia article on Levenshtein distance.

There's a TSQL implementation of the Levenshtein distance algorithm here.

Share and enjoy.

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EDIT 03-May-2012

Since writing my original response I've learned that Oracle includes the Levenshtein distance and several other "string similarity" functions in the UTL_MATCH package, which I believe is a standard part of the database. Documentation here. Perhaps not directly related to the original post (which was for SQL Server) but perhaps useful as many shops use multiple databases.

Answer 2

Have you looked into the Full-Text Search feature in SQL Server? I know this is not exactly what you asked for. Its just that the SOUNDEX() function is used to find similar SOUNDING names (EX: SMITH and SMYTHE sound the same). In a search engine, however, how a word sounds is less important than the search words themselves. Full-Text Search also lets you use synonyms (allowing you to specify certain words that mean the same thing within your application's context), and have them automatically considered during your search.

Look at these pages for more information about Full Text Search in SQL Server:

Introduction to Full-Text Search

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