Database Management
Reference Manual
Introduction to Database Concepts
:
Data Access Control (DACs)
: Effect of Modifications on Dynamic Rules
Effect of Modifications on Dynamic Rules
A dynamic rule will automatically respond to changes which affect the attributes referred to in the rule.
For example, we set a rule on YLEN of /MYBOX to be (YLEN OF /FRED * 2). Thus if YLEN on /FRED changes then YLEN on /MYBOX will be updated automatically. However there are reasons why the automatic propagation of dynamic rules may fail, as follows:
1.
The elements are in different DBs and the DB containing /MYBOX is not in the MDB
2.
The elements are in different DBs and the DB containing /MYBOX is read only
3.
It is not possible to claim /MYBOX
4.
/MYBOX is locked
5.
There is a DAC preventing the change
Note also that only static rules are not automatically updated. For these reasons there are commands to verify that rule results are up to date.
1974 to current year.
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