How to implement auto suggestion (auto complete) f

Question

I want to implement auto suggest functionality in Google App Engine (GAE/GWT).

The client side of the implementation works fine with GWT SuggestBox and RPC. My main issue is the server side of the implementation. I tried the Google search API but it seems that there is a limitation of 250MB of total indexed data and the search can be performed on complete words and not parts of each word!

How should I approach this? I read that lucene or solr is not supported in GAE. I would appreciate your thoughts on this.

Answer 1

You can achieve a basic text search using these techniques described here: http://googlecode.blogspot.com.br/2010/05/google-app-engine-basic-text-search.html

In short:

Build a query using content >= yourQuery && content < yourQuery + "\ufffd", where the content property of your entity can be a String or a List of Strings.

Answer 2

I've taken this approach and it works fine for me:

1. Split up text into separate words. Get rid of duplicates, special characters and short words (in, of, and, etc..).

2. Add this list of words to entity as a list property.

3. Search via text range query: listProperty >= wordPart && listProperty < wordPart + "\ufffd"