Re: Optimizing object materialization for 1:N relations

Danilo Tommasina <[email protected]> Thu, 07 Feb 2008 10:43:56 +0100
Newsgroups gmane.comp.jakarta.ojb.user
Organization RCS AG
Message-ID <[email protected]>
Hi Tino,

I think he meant, that you can load several ACLs with one query and use prefetched relationships for loading all depending ACLEntries for each loaded ACL.
Also in this case you will have only 2 Queries, but you will bulk load several ACLs

Bye
danilo

Tino Schöllhorn wrote:
> Hi Armin,
> 
> thanks for your reply. Do you think it would be worth a try to 
> materialize our objects with pure SQL - but after initializing them to 
> work with them with OJB?
> 
> Thanks for your opinion.
> 
> Regards
> Tino
> 
> Armin Waibel schrieb:
>> Hi Tino,
>>
>> Tino Schöllhorn wrote:
>>> Hi,
>>>
>>> we are using OJB-1.0.1 and evertything works fine. Now I have the 
>>> following situation:
>>>
>>> We have a security-mechanism which uses the classes ACL 
>>> (AccessControlList) and ACLEntry. One ACL has many ACLEntries. Now  
>>> when using the standard OJB-Materialization methods OJB uses 2 SQLs 
>>> to materialize on ACL. One for the ACL and one for the ACLEntry.
>>>
>>> Because we have MANY of those ACLs I am curious if it is possible to 
>>> overwrite the materialization-method so that just one SQL is used. I 
>>> thought about using "Prefeteched Relationships" but I noticed that 
>>> there are also 2 SQLs.
>>
>> The "Prefeteched Relationships" is useful if you search for more than 
>> one ACL, then OJB is able to reduce the queries to read the ACLEntries:
>> http://db.apache.org/ojb/docu/guides/query.html#prefetched+relationships
>> The upcoming version 1.0.5 use "Prefeteched Relationships" for all 1:n 
>> relations.
>>
>>>
>>> Any ideas or even example how I could achieve that?
>>>
>>
>> Sorry no.
>>
>> regards,
>> Armin
>>
>>> Kind regards
>>> Tino
>>>
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: [email protected]
>>> For additional commands, e-mail: [email protected]
>>>
>>>
> 
> 
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [email protected]
> For additional commands, e-mail: [email protected]
>