In DataDesigner, you can specify a list of domain values for each field. The domain values are usually constant or static text. For example:

 UserRole: Normal, Super, Admin
 Age: 5, 10, 25, 45, 60
 FirstName: John, Bruce, Teri, Sandy

There are times when you generate the test data set you may wish to randomly generate these values or write your own function to generate these values according to your own rule or convention.

DataDesigner provides a facility to allow you to call MScript functions or write your own MScript functions to dynamically generate domain values for the field.

For example:

 Age: $rand(5), $rand(6, 16), $rand(17, 35), $rand(36, 60), $rand(61, 120) 

The above example calls $rand() MScript function to generate a random number in the specified range when the test data set is generated. Each time when the test data set is re-generated, a different set of domain values are generated.

You may write custom MScript functions and call them just like MScript function example above. First you must add your MScript implementation java class to the field MSript Class. Once that's declared, you can use them as follows assuming your MScript Class contains the java function ageByGroup('group'):

 Age: $_ageByGroup('kid'), $_ageByGroup('teen'), $_ageByGroup('youngAdult'), $_ageByGroup('midAge'), $_ageByGroup('senior')