DeleteCascade on PostgreSQL

Ricardo Tedim <[email protected]> Wed, 13 Jul 2005 15:44:46 +0100
Newsgroups gmane.comp.java.enhydra.dods
Message-ID <[email protected]>
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Hi,

I'm doing some perfomance tests in a project running on top of the new 
Enhydra 6.4.1 (Tomcat version) and a PostgreSQL DB engine (7.3.9). I've 
noticed that on the DODS configuration that was installed with this 
Enhydra, the DeleteCascade parameter for PostgreSQL is set to false. 
This means that the DB reference integrity will be guaranteed by the 
data layer generated by DODS, and for what I understood this is done by 
fetching (on DB) the objects that have references to the object being 
changed, and performing on them the required changes (if needed). So for 
instance if I have a DO named A that references B and I try to delete B 
using the DODS layer, this will result in following SQL operations:

1. Select B from DB and then delete it by invoking the delete method on 
its DO.
2. Select A from DB (triggered by DODS)
3. Delete A and B from DB.

If this integrity is guaranteed by the DB engine, the 2nd operation and 
part of the 3rd will be automatically  performed by the DB engine 
resulting in a performance improvement. This is what I wanted to explore 
in the project I'm in, but first I would like to know from you if 
there's any known issue related to the setting of this parameter to true 
(since by default it is setted to false).

Thanks in advance,
Ricardo Tedim




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