db-derby-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Rick Hillegas <Richard.Hille...@Sun.COM>
Subject Re: Lucene integration
Date Tue, 24 Mar 2009 18:55:38 GMT
Hi Geoffrey,

I'm hoping to have some time to look at Lucene integration after we put 
10.5 to bed. In the meantime, I was wondering if you have any experience 
with implementations of Lucene Directory which place the Lucene indexes 
inside a relational database? According to the following link, people 
have been disappointed with the performance of this approach (don't know 
what that means)--at first blush, however, the approach seems like an 
attractive way to keep the Lucene indexes transactionally consistent 
with the original character data:



Rick Hillegas wrote:
> Hi Geoffrey,
> I'm on the road right now but I'd like to make some suggestions after 
> I gather my thoughts and get over my jet lag. I think that it is 
> definitely possible to hook into the query processing layer in order 
> to fork the tuple stream so that a listener process can populate the 
> Lucene indexes. I think that scraping the replication log stream would 
> raise a lot of issues around when work is really committed vs. when 
> savepoints are rolled back, and I would recommend against that approach.
> Regards,
> -Rick
> Geoffrey Hendrey wrote:
>> Ok, well on to plan B then. Is there some stage in the preparation of 
>> inserts, updates, and deletes at which the logical identity of a row 
>> is established? That could be a good place to provide a lucene hook, 
>> or a more general interceptor.
>> On Mar 18, 2009, at 6:55 AM, Jørgen Løland <Jorgen.Loland@Sun.COM> 
>> wrote:
>> Geoff hendrey wrote:
>> I've been folowing knuts pointers and reading the docs on the classes 
>> that marshal themselves over the wire via their writeObject method.
>> So, question about this:
>> "Type=update, Table=employee, Page=4321, Index=4, field 3=50000"
>> Does the page and index, collectively, constitute a "row ID".
>> If it is always a constant, than these three field are sufficient to 
>> permanently identify the row, and we can use that information to 
>> consititute a document ID in lucene.
>> It's constant until the record is moved to another page (which means 
>> "no", really).

View raw message