C-1069 04-02 Record the if.. then.. logic of the
decision tree in this array, which has three columns. The unlabeled
columns are known as the comparison, action, and next value columns.
03-01 ZELEK 8/12/02
This help topic describes the basic format of the
Decision tab. If you encounter a Decision tab that contains Evaluate
Parameter or Evaluate property name, see Completing the
Decision tab (Advanced format).
At runtime, the system evaluates the if portion of
the array, starting at the top row, and continues as described here until
it reaches a Return
statement. If the system processes all
rows but does not reach a Return
statement, it returns the
Otherwise
value.
If the Redirect this Rule? box on
the Results tab is selected, this
circumstance-qualified rule is redirected and this tab
appears blank.
Understanding the rows
Each text box may contain a value, a
comparison operation for two values, followed by an outcome. The
comparison may be between two properties or between a property and a
constant value.
Click a field to make controls for that row or field visible:
- Click Collapse
All to hide subtree
structures, or a minus sign to hide subtree structures.
- Click Expand
All to show all subtree
structures, or a plus sign to display specific subtrees.
- Click the pencil icon () to review a property rule (for a field that
contains a property reference).
- Select a row and then click the, , or icons to insert, append, or delete a row. (Equivalently, use
the Insert ,
Shift + Insert , and Delete keys).
Field
|
Description
|
if / if value is
|
Enter a comparison using one
of the six comparison operators <, >, =, !=, >= or
<=.
The value may be a constant or a Single Value
property reference.
This field is not visible if the action field is set to
Otherwise .
|
(action)
|
Select an action from the selection list. The action you
choose determines which branch of this decision tree the system
follows at runtime when the condition to its left is reached and
evaluates to true. Select a keyword:
Keyword
|
Effect
|
Return
|
Causes this branch of the decision tree to end
processing when reached. If the system finds a
Return row to be true, the value in the
right column of this row becomes the result of the
decision tree evaluation.
|
Continue
|
Causes the next row of the decision tree to
be nested within this branch, The system reflects the
nesting by indenting the next row on the form display
and changing the arrow to
to point down to that indented
row. The context for the continue statement is the same
as for the current statement.
|
Call Decision Tree
|
Causes the system to evaluate another decision tree
rule, identified in the next field.
This choice may
not be present in all cases, depending on settings on
the Results tab.
If, at runtime, this decision table evaluates in a
backward-chaining context (the
AllowMissingProperties parameter to
the method is true), the system evaluates the called
decision tree rule in the same way.
|
Call Map Value
|
Causes the system to evaluate a map value rule,
identified in the next field. C-1782
This choice may
not be present in all cases, depending on settings on
the Results tab.
If, at runtime, this decision table evaluates in a
backward-chaining context (the
AllowMissingProperties parameter to
the method is true), the system evaluates the called
map value rule in the same way.
|
Call Decision Table
|
Causes the system to evaluate a decision table rule,
identified in the next field. C-1782
This choice may not be present in all cases,
depending on settings on the Results tab.
If, at runtime, this decision table evaluates in a
backward-chaining context (the
AllowMissingProperties parameter to
the method is true), the system evaluates the called
decision table rule in the same way.
|
Otherwise
|
Select Otherwise only as the bottom,
final choice in a set of alternatives, marking the
final choice. The value in the right column of this row
becomes the result of this decision tree
evaluation.
|
|
(next value)
|
Identify a target based on the action value.
If you
selected Return as the action and the Results tab is not blank, select one of the
values listed on the Results
tab.
Otherwise, enter a value or expression here that allows
evaluation of the decision tree to continue. 03-02
C-344 You can reference a property on any page, but be sure
to enter any page you reference on the Pages & Classes tab. Enter a value that
depends on the action value keyword:
Return or Otherwise —
Enter an expression for the result of this decision tree when
this row is the final one evaluated.
Call Decision Tree — Select another
decision tree rule. The result of that rule becomes the
result of this rule. (This choice may not be present in all
cases, depending on settings on the Results tab.)
Call Map Value — Select a map value
rule. The result of that rule becomes the result of this
rule. (This choice may not be present in all cases, depending
on settings on the Results tab.)
C-1782
Call Decision Table — Select a
decision table rule. The result of that rule becomes the
result of this rule. (This choice may not be present in all
cases, depending on settings on the Results tab.) C-1782
This input field does not appear when the action value is
Continue .
Click the pencil icon () to open a
referenced decision tree, map value, or decision table rule.
|
|
Click to access an
optional array of properties and values. Clickto hide this array. (This choice may not be
present in all cases, depending on settings on the Results tab.) C-1675 R-17048
When the decision tree rule evaluates and this row is the
source of the results, the system also recomputes the value of
the target properties identified in this array. Order is
significant.
|
Property
|
Optional. Identify a property
reference to be set. |
Value
|
Enter a value for that property. |
Otherwise
|
|
Return
|
Optional. Enter an expression defining a value to return when
the decision tree evaluation does not return another value. When
the Allowed Results list on the Results tab is not blank, this field is required
and limited to one of the constant values listed on that
tab.
If this field is blank and no other return value is computed,
the system returns the null value.
|
About Decision Tree
rules