Modeling Business Rules - High-Performance Web Databases: Design, Development, and Deployment - page 148

Exhibit 10-5. A timer.
enforced; if the condition yields false (or null), rule #22.2 is not enforced (i.e.,
must yield null). Rule #22.2 may be an enabler for some other rule (not shown),
which now also will be dependent (indirectly) on the yield of condition #22.1.
Inclusion Rules
The second manner in which rules may be interconnected in building-
block fashion to model more complex business rules is for one rule to be
Exhibit 10-6. A yield rule.