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From Rahul Dwivedi <Rahul.Dwiv...@Sun.COM>
Subject Re: [ANNOUNCE] Apache Derby released
Date Fri, 24 Aug 2007 20:14:10 GMT
Basically i am requesting for an implementation similar to what you 
mentioned in the second case. I think that implementing the second 
option will have some performance benefit, if large amount of data is 
moved or copied from one table to one or more tables in the same schema, 
in addition to the benefits of first case.

now about the questions related to LOB updates it's some thing that 
probably needs more discussions but in my view if a LOB is updated it 
can be treated as a different LOB with different locator.


Øystein Grøvlen wrote:
> Rahul Dwivedi wrote:
>> Are there any plans for implementing such a feature where lob 
>> locators are stored in tables and LOB are stored some where else, or 
>> such similar functionality to enhance performance with multiple lobs 
>> in single table.
> I do not think that anyone has so far indicated that they have any 
> plans for this. However, I would very much like to understand better 
> what you are requesting.
> If I understand you correctly, your main objective is that if LOBs are 
> stored outside the table, a table scan will be much quicker.  Is that 
> what you are thinking of?
> Others have asked for locators in order to save space if two columns 
> are referring the same LOB.  That raises the question of what should 
> happen if a LOB is updated (e.g., through JDBC by Blob.setBytes).  
> Should that update be reflected by all columns referring the Blob, or 
> just the column being updated.
> -- 
> Øystein

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