Thks for the wonderfull featured Tutorials.I have successfully implemented most of it.
well I am in need of details of various setting required if as option oh Hypersonic Database / I am using postgresql7.0 need to used.
The details i have done are.
1. postgressql.jar file have copied in jbossx.x.x\lib directory.
2. postgres-ds.xml file have been edited and copied in deploy directory appr.
well further i have bit confusion how my
standardjboss xml files should i edit.
I purposely not moved further on doing R&D but it would be great help to save my time .
THks in before
Read the wiki page on batch-cascade-delete which describes why cascade-delete is the default.
I did exactly that. I read your article on WIKI and found how to use <batch-cascade-delete/>. Without this article I wouldn't even know about <batch-cascade-delete/> DD parameter. (BTW, I tried to do some changes on this article but encountered difficulties to submit it. WIKI editor cripled my response! Something is wrong with this WIKI editor! The preview looked just fine but when I submitted response it was clipled! Take a look.)
You explained how JBoss manages cascade deletion of related records:
* destroy relationship;
* synchronize the state (set foreign key fields to NULL in the database to be able to remove the parent);
* remove the parent instance;
* for each child repeat the procedure starting from 1.
IMHO this is wrong approach. In big majority of cases you will not be able to destroy relationship regarding database referential integrities. Also, more than often foreign keys are NOT NULL columns. So this listed approach will work only with database models without real integrity constraints implemented in it. Ask DBA's and other people working with DB's what they think about databases without referential integrities!
My question is what is the difference if I set <cascade-delete/> or not? As it has been mentioned, I tracked JDBC traffic of JBoss and find out that there's no difference for JBoss if I set <cascade-delete/> or not! JBoss sends the same SQL trying to destroy relationships regardles of <cascade-delete/>.
I restored the page. Read starting from "The EJB2.1 spec defines the cascade-delete protocol in "10.3.4.2 Cascade-delete" as:"