db4o Developer Community

Hi,

I am currently integrating db4o with Spring.NET (using Spring.Data classes from the CVS sandbox, if some of you wonder).

However, several things scratch my mind :

1) Concerning the connection Creation : is there a generic Factory for creating connections, no matter whether the connection opens an ObjectContainer directly on a file, or uses an embedded or even remote server.
I am roughly speaking about an equivalent of a JDBC "Datasource" , that allows Spring to ds.createConnection() when it needs one.

2) Is there any plan to create a "pooled" (a.k.a commons-dbcp) implementation of such a Datasource ? I don't think it is realistic to run a publicly available website using non-pooled connections, is it ?

3) Concerning Queries...
The spring-enabled DAO that needs to perform a query DOES NOT and MUST NOT know the ObjectContainer instance it will work on. This is up to the Db4oTransactionTemplate to get a connection, and synchronize an existing transaction to it. This implies that
 - db.query() is impossible => no way to get a SODA query
 - Native queries are possible, but I am worried by the actual performance of this kind of queries. Optimizing them means that bytecode/IL analysis is necessary, so I doubt it is ready yet, is it ?

Thanks a lot for any suggestion,
Sami

Just some additional note :
When I say that SODA queries are not possible, it is because since the DAO cannot get an instance of an ObjectContainer (Spring-way of doing things), then it cannot express its query.

However, is a SODA query actually connection-dependant ? Because if it isn't, then it would be wise to be able to create it differently.

Native queries are performant and optimized already. They're done and working. For now, all simple queries are optimized. Many special cases are also optimized too, but we can't cover everything. If you've got a slow query, try simplifing it, or finding which operation in your query is the one that cannot be optimized. Let us know what it is, and maybe it'll be in the next release.

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Eric Falsken » db4objects

OK, thanks for the reply. By looking at the announces, I was unsure whether everything was optimized, or whether the optimization will be developed in the future :) Looks like it's both :)
great job ! And thank you very much for your work

Sami Dalouche