Even if you can connect, it is read only. One approach to consider is an observer, and replicating the data on a cache, but this comes with significant architecture considerations. Another approach is to just use the API's, the native ones not custom built restlets, they are very fast when used right. But the limit you will run into there is the dataset size.... you may end up in SOAP world and SOAP is great in Oracle world. To help yourself there, train a model on the syntax and codegen most of it.