Cache Coherency in Oracle Parallel Server
نویسنده
چکیده
These advantages do not come for free. The challenge of this architecture (as of any clustered or distributed architecture) is to provide data coherency for the independent users of the system. The way to do that is to use locking. Oracle uses multiple level locking: row locks on transaction levels, instance locks within instances, and global locks among the instances. The latter are specific to Oracle Parallel Server.
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