lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Dawid Weiss (JIRA)" <>
Subject [jira] Created: (LUCENE-1622) Multi-word synonym filter (synonym expansion at indexing time).
Date Tue, 28 Apr 2009 18:30:32 GMT
Multi-word synonym filter (synonym expansion at indexing time).

                 Key: LUCENE-1622
             Project: Lucene - Java
          Issue Type: New Feature
          Components: contrib/*
            Reporter: Dawid Weiss
            Priority: Minor
         Attachments: synonyms.patch

It would be useful to have a filter that provides support for indexing-time synonym expansion,
especially for multi-word synonyms (with multi-word matching for original tokens).

The problem is not trivial, as observed on the mailing list. The problems I was able to identify
(mentioned in the unit tests as well):

- if multi-word synonyms are indexed together with the original token stream (at overlapping
positions), then a query for a partial synonym sequence (e.g., "big" in the synonym "big apple"
for "new york city") causes the document to match;

- there are problems with highlighting the original document when synonym is matched (see
unit tests for an example),

- if the synonym is of different length than the original sequence of tokens to be matched,
then phrase queries spanning the synonym and the original sequence boundary won't be found.
Example "big apple" synonym for "new york city". A phrase query "big apple restaurants" won't
match "new york city restaurants".

I am posting the patch that implements phrase synonyms as a token filter. This is not necessarily
intended for immediate inclusion, but may provide a basis for many people to experiment and
adjust to their own scenarios.

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message