Re: RE : [mdr-dev] RE : [mdr-dev] RE : [mdr-dev] RE : [FwdT: Re: [mdr-dev] JDBC persistence]

I'm going to be facing a similar problem soon, since in the Farrago DBMS 
project, MDR manages the metadata and a separate component manages 
relational data storage.  The reason I developed the JDBC storage layer 
is so that I can unify the two.  Immutable boot metadata about system 
tables will be stored in an MDR btree file; user data and metadata about 
user tables will be stored in relational tables.  In order to be able to 
mix DDL and DML in one transaction, I'll need to make the MDR 
transaction boundaries match the Farrago transaction boundaries.  I can 
solve the problem since I have top-level control, but it would be 
simpler if the components could participate in a larger transactional 
context as you describe.

JVS

Olivier RICHAUD wrote:
> [Slight out of topic]
> Of course, this is far beyond a JDBC persitency layer, but this should be
> the right direction for MDR, especially in standalone mode. And this is not
> only address Jboss, but any application server. This is the problem of this
> kind of tool : none integrates a standard transactional mechanism and all
> develops their transactional mechanism. For example, this is the case in our
> tool : this would have been so easy if the XML database, the persistent
> objects and the MDR had a way to join the current transaction.