Populate() Details

Formally, the Populate() class method has the following signature:

classmethod Populate(count As %Integer = 10, 
                     verbose As %Integer = 0, 
                     DeferIndices As %Integer = 1, 
                     ByRef objects As %Integer = 0, 
                     tune As %Integer = 1,
                     deterministic As %Integer = 0) as %Integer

Where:

count is the desired number of objects to create.
verbose specifies whether the method should print progress messages to the current device.
DeferIndices specifies whether to sort indexes after generating the data (true) or while generating the data.
objects, which is passed by reference, is an array that contains the generated objects.
tune specifies whether to run $SYSTEM.SQL.TuneTable() after generating the data. If this is 0, the method does not run $SYSTEM.SQL.TuneTable(). If this is 1 (the default), the method runs $SYSTEM.SQL.TuneTable() for this table. If this is any value higher than 1, the method runs $SYSTEM.SQL.TuneTable() for this table and for any tables projected by persistent superclasses of this class.
deterministic specifies whether to generate the same data each time you call the method. By default, the method generates different data each time you call it.

Populate() returns the number of objects actually populated:

 Set objs = ##class(MyApp.MyClass).Populate(100)
 // objs is set to the number of objects created.
 // objs will be less than or equal to 100

In cases with defined constraints, such as a minimum or maximum length, some of the generated data may not pass validation, so that individual objects will not be saved. In these situations, Populate() may create fewer than the specified number of objects.

If errors prevent objects from being saved, and this occurs 1000 times sequentially with no successful saves, Populate() quits.