Report Builder Using Power Bi Data Source, Parameters to decide which filter to use.(DAX)

Ok.... here's one for you.

Simple query really but it depends on a Parameter if "Child" Account is to be added to the end result or not..

so I have a Qry in Power Bi ... has Account Code, Parent_account_code, IS_Parent and a Value.

On my Paginated report I have a Parameter to Choose Account Code and one to say Y or N to adding Child Account.

If Yes.. then my @AccountCode parameter is run against the Parent_Account_Code Column, if not then against the Account_Code Column.

How... in the Query Designer do I do that?

If @Include = "Y" then

EVALUATE
CALCULATETABLE ( 'INV', INV'[PARENT_ACCOUNT_NUMBER] = Account_Code)

 ELSE

EVALUATE
CALCULATETABLE ( 'INV', INV'[ACCOUNT_NUMBER] = Account_Code)

something like that at all?

Kind Regards Mike Taylor