[From Builder UK
Using Oracle to access external, non-Oracle databases transparently can be tricky. We show you how.
Oracle's Heterogeneous Services layer is a way for an Oracle database server to access data on external, non-Oracle databases transparently using Oracle. For example, you can configure Heterogeneous Services and SQL*Net to access a Microsoft Access database through ODBC or OLE DB. Afterwards, you can query the table as if it were in a remote Oracle database:
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