HP 3000 Manuals

HP ALLBASE/4GL Developer Reference Manual Vol. 2

Decision Table Relationships Screen 

This screen allows you to define the columns of the decision table.  Each
decision table column defines one combination of possible outcomes for
the decision table questions, and the sequence of actions to be performed
if that particular combination of outcomes occurs.  A decision table can
have up to 31 columns.

You must complete the entire screen to define each column of the decision
table.

Screen Image 


            

Field Descriptions 

Decision Table Name.  Enter the name of a decision table whose questions
and actions have already been defined on the appropriate screens.

Secured.  Display-only field indicating the status of the Secured field
on the decision table header screen.

Column Number.  Enter a number in the range 1 to 31, specifying the
column to be defined or modified.

Amendment Mode.  May be either:

   A    add a new column or amend an existing column.

   D    delete an existing column.

The next set of fields defines the interpretation of each question
required for this column and the sequence of actions to be executed if
the outcomes for the questions match the outcomes specified for the
column.

Question.  For each decision table question, specify one of the following
options in the response area:

   Y    the question must be true.

   N    the question must be false.

   -    the question has no bearing on this column (that is, don't care).

Possible Action.  These fields display the specified decision table
actions for reference purposes.

Order of Execution.  In these fields, you can specify the sequence in
which HP ALLBASE/4GL executes the decision table actions.  For any given
decision table column, HP ALLBASE/4GL only executes the decision table
actions if the results of all the decision table questions match the
results you specify for that column.  Refer to Additional Information.

To specify the sequence in which HP ALLBASE/4GL executes the actions,
enter a number from 1 to 8 against each action.  Use each number once
only.

Enter a zero against an action if you don't want the system to execute
that action.

Column Definition.  Documentation field.  Enter a description (up to 20
characters) to identify the purpose of the column.

Function Keys 

f1       Header  Cancels the current screen and displays the decision
        table header screen.

f2       Questions  Cancels the current screen and displays the decision
        table questions screen.

f3       Actions  Cancels the current screen and displays the decision
        table actions screen.

f4       Generate D.Table  Generates the decision table.

Additional Information 

When HP ALLBASE/4GL executes a decision table, it scans the columns of
the decision table, starting with column number one.  HP ALLBASE/4GL
tests each column in turn until it detects a column that matches the
actual outcomes of the decision table questions.

HP ALLBASE/4GL executes the actions specified for this decision table
column in the sequence you have specified, and then terminates processing
of the decision table.  This means that if you have defined two or more
decision table columns that may be satisfied by a particular combination
of outcomes, only the lowest numbered column will be executed.  This
situation may occur if you have specified the don't care result for a
question in one column, and also specified a more restrictive set of
conditions by specifying Y or N for the same question in a different
column.

Note that if one of the actions executed by a decision table is a process
or a menu, the decision table is terminated immediately.

MPE/iX 5.0 Documentation