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+2 A:

You need not store each term within a separate field. Lucene creates tokens out of each term (if you are using a whitespace tokenizer) hence allows for great flexibility of search.

To your question about:

Example field : "generic brand strength"

Should match searches : "generic brand strength" "brand generic strength"

The above query will return both the results, the latter with a lower score for obvious reasons. However, "gen bran str" "bran generic str" ... etc. is tricky, since it appears the terms are not standard "stems" in which case you can use a stemmer analyzer.

The simplest approach would be to:

Split your query phrase by the white space, so you have a string[]
Use a Booleanquery and create a query for each term appending a wildcard at the end.

Something like:

string[] terms = query.split(" ");
BooleanQuery bq = new BooleanQuery();

foreach(string term in terms)
 bq.Add(new Query("FieldName", term + "*",...);

There are better query types such as SpanQuery, DisMax etc. , but since you mentioned a noob alert, think the above is simplest (although prolly not most elegant) approach.

HTH

Mikos 2010-07-29 12:03:10

+1 for the wildcard solution. Easiest, although it might produce performance problems for large indexes.

bajafresh4life 2010-07-29 16:28:22

Is there a notable difference between using a wilcard query (by appending an asterisk) and the PrefixQuery? They seem identical to me. Thoughts? Do they basically boil down to the same thing?

berko 2010-07-30 03:37:53

Yes they are identical. The Javadocs describe it thus:"A Query that matches documents containing terms with a specified prefix. A PrefixQuery is built by QueryParser for input like app*."

Mikos 2010-07-30 11:20:22

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Query types within Lucene

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