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From Karl Wettin <>
Subject Re: local object storage
Date Sat, 19 Apr 2008 22:47:20 GMT
It should not be too hard. I was looking at ByteBuffer and FileChannels 
today but didn't figure out how to write it so it will automatically 
grow with more file segments as they are required.

Anyone that can fix something like that in a few minutes?

The tree is abstract for persistency. Implementations use a combination 
of visitors and factories and it is quite simple to add support for 
anything else. Derby?

I often say that BDB is the perfect balance between OODBMS and RDBMS. 
All entities are serialized with all aggregated data and associated with 
a primary key in a hashtable on disk. Thats it.

We could implement our own transactionless variant that use Writable for 
serialization. Is it possible to seek on DFS?


Grant Ingersoll skrev:
> Yeah, I think it does the good ol' download process, meaning it isn't 
> compatible :-(
> How much work to roll your own?  Or, I suppose, find something that is 
> compatible.
> On Apr 19, 2008, at 12:45 PM, Karl Wettin wrote:
>> trunk/contrib/db/bdb-je to be precise
>> but I notice it is not in the libs there.
>> Grant Ingersoll skrev:
>>> Is that what Lucene Java contrib/db/bdb uses?  Or at least a 
>>> different version?
>>> On Apr 18, 2008, at 5:58 PM, Karl Wettin wrote:

>>>> Grant Ingersoll skrev:
>>>>> What's the license?
>>>>> On Apr 18, 2008, at 5:37 PM, Karl Wettin wrote:
>>>>>> I need to persist my tree is some way. Was thinking ad hoc:
>>>>>> a file with branch node pks
>>>>>> a file with branch node records
>>>>>> a file with leaf node pks
>>>>>> a file with leaf node records
>>>>>> an optional file with node mean instances
>>>>>> Will probably start with BDB JE though. Any comments to adding 
>>>>>> that to the libs?
>>>>>>    karl

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