Object-Relational Mapping
If you want to take advantage of using an ODBMS in the middle tier and have one or more existing relational databases, you will need to map data from a relational format to an object format.

So, if you need to map, consider using an object-relational mapping product. They will save you time and reduce the number of defects in your mapping. For more information on object-relational mapping products, click here.
An object-relational mapping product is shown at the left of this figure. It handles the mapping and has a cache much like an ODBMS. Data is mapped to the ODBMS and from the ODBMS based on the application needs. The ODBMS provides high-speed performance for the Internet.
For more information on mapping details, see mapping.
For how to use object-relational mapping with Java application servers, see enterprise architectures using Java application servers.
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