The Oracle Database In-Memory option is a new memory-optimized database technology that implements an in-memory columnar data format to deliver extremely fast SQL processing.
The Oracle Database In-Memory option requires an In-Memory column store, which is a new component of the SGA called the In-Memory Area.
You can allocate as little or as much memory as you wish to the In-Memory Area. The larger the In-Memory Area, the greater the number of objects that can be populated into the In-Memory column store.
Oracle Database In-Memory Option goals are “Real Time Analytics”, “Mixed Workload OLTP”, “Easy To Implement” and “No Changes in Applications”

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