# Implementing the Child over 3 years old is free promotion step

## Creating the rule

Create a new Guided Rule that you call YougestUnder3yearsOldFree

then Add a new Constraint

![](/files/-M-FWc1-aWaHAaIVJlkn)

![](/files/-M-FWc111M68SoYNXsJp)

Select the List class. Click on the "There is a list.." and the click on the Expression Builder button

![](/files/-M-FWc13YXlynpq34uFu)

on the first "Choose" select the size() function and on the second "greater than"

![](/files/-M-FWc15sJ8A1djSCXEP)

Then click on the pencil ![](/files/-M-FWc17ZCDSKhnQ3fhp) Click on the "From Collect" link and then chose the person fact type

![](/files/-M-FWc19sPK7gSHfTro7)

![](/files/-M-FWc1B0eRAbUYttBLH)

Then click on the "All Person with" link and select the age attribute and add the following constraint.

![](/files/-M-FWc1Dne0lwggf1MAQ)

Then Add a new constraint of type Accumulate

![](/files/-M-FWc1FbAprmS3tzSbD)

And select the Number type from the add a pattern link.

![](/files/-M-FWc1HQMKIpWr_TS-P)

Then make the rule look like this

![](/files/-M-FWc1JKCxPAZRr6wkB)

## Creating rule to insert a period

![](/files/-M-FWc1LphV0MrAaZqyP)

Create a drl file with the following content

![](/files/-M-FWc1NYIhzSU5WyD2k)

## Creating rule to start a process

To be able to start a process from a test scenario, we want to insert an object and set a attribute that would be the process id we want to start. So we first create a new Item of type Data Obkect that we shall call StartProcess. And we should add a field called procesId of type String

![](/files/-M-FWc1PDbDlF9XcMzpC)

Then we shall create a guided rule called StartProcessRule as follows. In the Then add free form drl ![](/files/-M-FWc1RTj3mve7vQEMv)

![](/files/-M-FWc1T-uT85gF0rNsX)

## Testing the rule

Create the test scenario by inserting Objects like follows.

![](/files/-M-FWc1V2TCeBfBsa_3F)


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