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From Anurag shekhar <Anurag.Shek...@Sun.COM>
Subject Re: Using StorageFactory to create temporary files
Date Thu, 03 Aug 2006 13:15:03 GMT
Let me explain why I need a temporary file. I need a storage where 
blob/clob can be stored before writing into the table. As the size of 
lob can go upto 2gb its not possible to keep it in memory. I am using 
the temporary file to keep the byte/string in case the the size grows 
more than 4k.

So the temporary file will be created and accessed from the jdbc driver. 
I decided to use StorageFactory because it already have the nessasary 
permission for disk i/o. In case derby is running on a special storage, 
the StorageFactory will be aware of it and will be able to create 
temporary file for that device.
Mike Matrigali wrote:
> This is an unexpected usage, this was never designed for that purpose.
> It was originally designed as a module only to be used underneath the
> store module.  The purpose was to allow alternate implementations of
> the underlying filesystem.
> I wonder why straight java i/o stream interfaces were not used?  Is
> there anything being provided by the StorageFactory that a direct
> use of java io does not easily provide?
> I think it would be especially a bad idea to use the storage factory
> on the client side of network server as it is going to draw in a lot
> of other stuff not currently needed by the client jar.
> Rick Hillegas wrote:
>> The patch attached to DERBY-1341 uses the StorageFactory to create a 
>> temporary file on behalf of the embedded JDBC layer. Is this usage 
>> OK? Does this violate some assumptions about what server layers are 
>> allowed to use the StorageFactory?
>> Would appreciate guidance here. I am out of my depth.
>> Thanks,
>> -Rick

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