Definition of irrigation. 1  1 : the therapeutic flushing of a body part with a stream of liquid. 2  2 : the watering of land by artificial means to foster plant growth.
Answer: To start with, Oracle Real Application Clusters (RAC) are a database system involving a configuration of multiple hosts or servers joined together with clustering software and accessing the shared disk storage structures.
The combined processing power of the multiple servers can provide greater throughput and Oracle RAC scalability than is available from a single server. Figure 1-1 shows how Oracle RAC is the Oracle Database option that provides a single system image for multiple servers to access one Oracle database.