Google App Engine JDO queries referring to other tables

Question

I have entity project that has list of task entities. I know project entity id and now I need to get list of project tasks (tasks contain project id). How can I make that kind of query in GAE with JDO?

Answer 1

Without a specific example I can only provide generic how-to info.

Look at this series:
http://www.ibm.com/developerworks/java/library/j-gaej1/
http://www.ibm.com/developerworks/java/library/j-gaej2/index.html
http://www.ibm.com/developerworks/java/library/j-gaej3.html
Specially the last two. They describe very well how to use the Persistence engine.

I think that what you are trying to do is create a relationship between two entities. That is tricky, but you can find some info here: http://gae-java-persistence.blogspot.com/

in addition to the GAE docs, which are here:
http://code.google.com/appengine/docs/java/datastore/relationships.html