Oracle and DB2, Comparison and Compatibility/Process Model/Consistency
In the section on database operation, great emphasis was placed on database consistency. There are whole suites of processes in the DBMS dedicated to preserving database consistency during its normal course of operation. The objective is that consistency is enforced by never allowing any operation to compromise consistency. Since consistency is so important, and there are things outside ‘normal’ database operations that can affect database consistency (power outages, power spikes, media failures etc.) all databases have additional processes that can be run against the database to check that the database is consistent, and in some cases rectify inconsistencies. Referred to earlier as a ‘Belt and Braces’ strategy, this may also be described more accurately as ‘Trust, but Verify’.