Show
all
A circumstance is an optional qualification available for all
rules. Using a circumstance allows your application to support multiple
variants of a rule. For example, variations of an ordinary rule instance
can be created for different customer status levels or for different
geographic locations.
Circumstance
qualified rules
A circumstance-qualified rule instance (often referred to as
a "circumstanced rule") is always based upon an unqualified
rule instance ( base rule ). You can circumstance a base rule
with a single property and its value, or with multiple properties and
their values (called multivariate circumstancing ). The
circumstanced rule is selected by rule resolution if the value of the
circumstance property on the rule matches that property's value on
the clipboard at runtime.
On many displays, a icon
identifies a circumstance-qualified rule instance. A icon identifies a base rule instance that
has one or more circumstanced instances. The rule form for a
circumstance-qualified rule displays the property and its value next
to the Circumstance label located in the top right area of the
form.
Example
Assume that you have difference pricing levels for your customers.
You first define a base pricing rule for all customers. Then you
qualify the base rule by creating circumstanced rules for customers at
different buying levels. The property .CustomerType
is
part of the customer order and has values of "Silver" and
"Gold". In this example, a customer has purchased a $100
item. Using the property and values, you create circumstance-qualified
instances of the base rules as shown here:
- BasePrice rule — if .CustomerType=(none), then Price
=$100
- BasePrice circumstance 1 — if .CustomerType =
“Gold”, then price = $100 - 25%
- BasePrice circumstance 2 — if .CustomerType
=“Silver”, then price = $100 - 10%
When the system processes the order, the value of that property
dictates which rule is run and thereby determines the discount (if
any) the customer receives.
For information on how rule resolution processes circumstanced
rules, see How the system finds rules
through rule resolution. See also the Pega Developer Network
article PRKB-25168 About rule resolution.
Contrasting
single-value with multivariate circumstances
If you use a single circumstance property, you define the property
name and its value directly in the Save As form.
PROJ-1166If you use multivariate circumstancing, you two rules in the Save
As form:
Multivariate circumstancing enable you to specialize a rule by
more than one feature. For example, an insurance company may be
required to collect, for every state, claims that exceed a specific
amount and the method by which the claims were conveyed (letter,
phone, email, and so on). Another example may be the need for a rule
that is specialized by an age range and not an absolute value.
Creating a
circumstance-qualified rule
To create a circumstance-qualified rule, first define an
unqualified or base rule instance (with the Circumstance values left
blank). Then use the
toolbar Save As button ( ) to create a
second rule qualified by a circumstance. If the original rule has an
Applies To class as an initial key part, the
circumstance-qualified rule must have the same Applies
To class or a subclass derived from that class. C-2441
GENTJ
For instructions on how to create circumstance-qualified rules, see
these Pega Developer Network articles:
- PRKB-25172 How to create a rule with a single circumstance
property
- PRKB-25173 How to create a rule with multiple circumstances
properties
Finding
circumstance-qualified rules
F.Karachi, v5.4 Select> Process and Rules > Tools > Find Rules > Find by Circumstance to BYRNB 2/23/10 create a list view report comprising
single-property and multiple-property circumstanced rules. You can
filter the report by searching on the following default circumstance
properties: U.S. State Codes, Channels, and
Customer Level. You can also search for
circumstance-qualified rules by entering text used in key parts
(Applies To or Name) in the
Name Contains field.
For more information on how to report on circumstanced rules, or
how to add or change the circumstance property columns for the report,
see the Pega Developer Network article PRKB-25220
How to find rules with a specific circumstance .
Redirection
For decision tree, decision table, and map value rules, you can
redirect one circumstance-qualified rule to another
circumstance-qualified rule (a peer with the same base rule), to
reduce the number of distinct rules that you need to maintain. Select
the Redirect this rule checkbox on the Results tab.
Notes
Circumstances are available only for certain
rule types — those with the Allow Selection based on
Property Rules? box selected on the Class form defining the
rule type. As of V5.4, you can circumstance-qualify
Declare-Constraints, Declare-Expression, and
Declare-OnChange rules.5.4, proj-823
You can circumstance-qualify Rule-PortalSkin rule types. V6.1, grp-5980, proj 242 You cannot
use circumstances with a final rule. MARIK 8/16/03 REMOVED The RuleSet Version of the circumstanced rule must be the
same as or higher than the RuleSet Version of the base rule. If you
revise a base rule (placing the new one in a version that has a higher
number than the circumstanced versions), you must copy (and revise if
needed) each circumstanced rule into the higher-numbered version also.
CLINIC 8/25/06
If a circumstance-qualified stream rule
contains JSP tags (rather than directives), the base rule must also
contain JSP tags rather than directives. Conversely, if the
time-qualified rule contains directives, the base rule must contain
directives. B-20380REMOVED (per S.Stewart 5/2/08): You
can't check out a circumstance-qualified rule at a time when the
base rule is already checked out by you or by anyone. Similarly, you
can't check out a rule that is a base rule when you or another
developer has a related circumstance-qualified rule checked out.
B-25517 BUG1755 B-20574
If two rules with the same Applies
To key part and family name are both unqualified and each has
one or more associated property circumstance-qualified rules, the same
circumstance property must be used. For example, if activity
MyClass.Alpha has an associated circumstance-qualified rule using
property .State, then another activity MyClass.Alpha cannot have a
circumstance rule with any property other than .State. B-19418
rejected and ERNSG 7/21/06
Database software supporting your Process
Commander system limits the number of columns that can occur in any
database table. When creating a Circumstance Definition rule, you may
not exceed this limit. See Pega Developer Network article PRKB-25322 Troubleshooting: "Exceeds the maximum
number of columns" when creating a Circumstance Definition
rule.
In releases before V5.2,
circumstance-qualified rules with a RuleSet version number lower than
the RuleSet version of a base rule were ignored (never selected)
during rule resolution. Starting with version V5.2, this is not the
default rule resolution behavior: you can copy a base rule to a higher
version without the need to also copy each of the (possibly many)
qualified rules associated with the base rule into that higher
version. If desired, you can revert in specific cases to pre-5.2
behavior by selecting the Base Rule checkbox on the
form produced by the Availability toolbar button (). C- 2555
Use the Data-Circumstance-Duplicates.CircumstanceMultiples.ALL report to identify single circumstance-qualified rules that
incorrectly use two or more different properties. Such conflicts can
arise when rules are imported into a RuleSet that already contains
some circumstanced rules. B-20800 GENTJ 5/30/06 To access this report, select > Application > Inventory > Inventory Reports. Enter Rule
as the Category and circumstance as the search text.
|
base rule,
declarative rule,
family name,
final rule,
property
reference, qualified rule,
redirected
rule, rule
resolution, stream rule,
time-qualified
rules, withdrawn rule |
|
How to complete rule form keys with Save As
How the system finds rules through
rule resolution How
to change rule availability
About Circumstance Definition rules
About Circumstance Template rules
|
Concepts