check out the following link for the OJB ODMG API http://db.apache.org/ojb/docu/tutorials/odmg-tutorial.html
The container is defined in the repository.xml file. http://db.apache.org/ojb/docu/tutorials/mapping-tutorial.html -A On Fri, 2004-07-02 at 07:01, Martin I. Levi wrote: > Aren't you supposed to do something like: > > select A.a, A.b, A.B.c, A.C.d, A.C.D.e, A.C.D.f from A,B,C,D; > > ??? > > And THE BIG question is... when you perform an OQLQuery.execute() this > returns and Object what critery should I follow to choose the container > to store the resulting objects? > > > > On Thu, 2004-07-01 at 19:49, Auckyboy wrote: > > I'll take a stab at it. > > > > when performing OQL queries using OJB, you get back the complete object > > A with references to B, C and further objects if they exist otherwise > > they are null. > > > > Assuming you have the following objects.. > > > > A{ > > B b; > > int bId; > > C c; > > int cId; > > } > > > > and > > > > C{ > > D d; > > int dId; > > } > > > > > > D{ > > id; > > name; > > } > > Now you want A where B, C and D are defined... > > > > select a from A where bID != 0 and cId!=0 and c.dId!=0 > > > > this in effect would give you A where B,C and D are defined. > > > > However, as a suggestion, if you need to perform queries on A, B, C > > etc..its better to use... > > > > select a from A where c.d.name = "somename" > > > > > > HTH > > -A > > > > On Thu, 2004-07-01 at 10:19, Martin I. Levi wrote: > > > Hi! > > > > > > Well, here I am with the ODMG 3.0 book trying to perform OQL querys > > > through OJB but I really think I just dont get it. > > > Lets suppose I have a table A with FK to B and C where C has a FK to D > > > Something like this: > > > B > > > / > > > A > > > \ > > > C > > > \ > > > D > > > > > > Which are mapped to the objects A, B, C and D. > > > Now I want to perform a query which in SQL would be: > > > > > > SELECT A.a, A.b, B.c, C.d, D.e, D.f > > > FROM A,B,C,D > > > WHERE A.B_key = B.B_key > > > AND A.C_key = C.C_key > > > AND C.D_key = D.D_key > > > ; > > > > > > My questions are... > > > 1) how could I do this on an OQL query through OJB? > > > 2) which kind of container should I use to store the result? An > > > ArrayList does always do the trick?, I suppose it doesn't... > > > > > > Any help will be useful! > > > > > > -- > > > Saludos, > > > > > > Martin I. Levi > > > > > > Centre TecnolÃgic de TransferenciÃncia de Calor > > > Universitat PolitÃcnica de Catalunya > > > www.cttc.upc.edu > > > > > > > > > --------------------------------------------------------------------- > > > 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] > > -- > Saludos, > > Martin I. Levi > > Centre TecnolÃgic de TransferenciÃncia de Calor > Universitat PolitÃcnica de Catalunya > www.cttc.upc.edu > > > --------------------------------------------------------------------- > 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]
