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From Robert Newson <rnew...@connected.com>
Subject Re: indexing values which might be null
Date Wed, 22 Jun 2005 00:57:02 GMT

An approach I've used successfully is to add a separate field called 
'empty' and include the names of other fields that are empty, e.g,

empty: subject

You can search for;

+empty:subject

for messages with empty (null) subjects.

This approach means you don't need to think of a magical value that (you 
hope) doesn't match other legitimate values. Additionally, you only add 
one new field to your index for any number of null-able fields.

B.

Otis Gospodnetic wrote:
> Hi George,
> 
> A field value needs to be indexed if you want to sort by it - see
> http://www.lucenebook.com/search?query=index+for+sorting .
> 
> As for null fields, you could use an empty string, or better yet, some
> "custom field value" that means "NULL" for your application.
> 
> Otis
> 
> 
> --- George Abraham <george.abraham.lists@gmail.com> wrote:
> 
> 
>>Hi,
>>I am using Lucene to index database content. I have two questions:
>>
>>1. Along with some of the fields that I want indexed, there are some
>>fields that I want stored (not indexed) in the index so as to return
>>with hits. However I also want to be able to sort a search result
>>using these non-indexed fields. Which method should I use in the
>>Field
>>class then?
>>2. As is usual with some database content, sometimes fields that have
>>to be indexed turn out to be null. Using the Keyword method, the
>>indexing procedure gives me an error that 'value cannot be null'. How
>>do I then go about this?
>>
>>Thanks,
>>George
> 
> 
> 
> ____________________________________________________________________
> Simpy -- simpy.com -- tags, social bookmarks, personal search engine


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