Is it possible to query and commit on the same persistence manager (i.e. same odb file) at the same time?
Query and commit simultaneously
Multithreading is fully supported by ObjectDB, so you can query and update the database at the same time using multiple threads.
However, if all the threads share the same EntityManager/PersistenceManager instance then operations are executed sequentially one after the other, because almost all the operations on the database are synchronized at the EntityManager/PersistenceManager level.
To have real concurrent operations, you have to use ObjectDB 2.0 (and not ObjectDB 1.0) and you have to use multiple EntityManager/PersistenceManager instances, usually one per thread. For efficiency, all the EntityManager/PersistenceManager instances of the same database can be obtained from the same shared EntityManagerFactory/PersistenceManagerFactory instance (which can be one per application/database).
ObjectDB - Fast Object Database for Java (JPA/JDO)