Explanation: Version 5.0 or
later versions of the product give the correct behavior. Consider the following
example: SET OutputRoot.MRM.A.B.C.D = 'ddd';
SET OutputRoot.MRM.A.B.C.E = 'eee';
IF OutputRoot.MRM.A IS NULL THEN
SET Environment.Variables.Result = 'NULL';
ELSE
SET Environment.Variables.Result = 'NOT NULL';
END IF;
In Version 2.1 the Environment.Variables.Result field
has the value of 'NOT NULL' and in Version 5.0 or
later it has the value of NULL.
The same is true if OutputRoot.MRM.A.B or OutputRoot.MRM.A.B.C were
tested against NULL. The reason for this is that these fields are MRM parent
fields, and this means that they do not have a value themselves.
Therefore,
it follows that these fields are implicitly NULL, and if tested against 'IS
NULL' return TRUE.
Note, however, that if you use XML parent nodes both Version 2.1 and Version 5.0,
or later, versions of the product return 'NOT NULL' for the Environment.Variables.Result field.