A process business rule can update a field based on the criteria within another field. For the example below we are going to want to assign records to certain users, based on the area of the UK they are in.
East Anglia records will want to be assigned to John
North East records will want to be assigned to Jane
First you will need to go to the Process Business Rules module from your module headers. If it is not there you can add this from the Admin menu's Select Module Tabs and Subpanels option.
Select Create
Name the process and choose your Target Module
Click Save and Design
In the dropdown below Conditions, choose the field you wish to evaluate. Which in our example will be Area
Below where you have chosen Area there are 2 columns, in the first column you will choose your operator. This case been ==(equals), !=(does not equal), >(greater than), <(less than), is, contains etc. For our example we will choose == (equals)
In the next column you will choose the the entry you wish to evaluate for. If the field is a dropdown you would choose between East Anglia and North East. If it was a text field then you can free type using the string option.
You will need to add a second "Conclusion" using the right hand side + icon.
In the first conclusion column you will need to select TRUE. you do this by selecting Constants - String, Number and Boolean - Type 1 and select Add Boolean
For the second conclusion column we need to choose the option to be changed to based on our condition. For the row where the condition is East Anglia, we would choose John. For the row where we have chosen North East, it would be Jane.
Click Save & Exit when done
We then need to add our business rule into a process definition. If you are unfamiliar with Process Definitions you can find instructions here. The only difference between this article and the linked article is you need to make the action in step 9 a Business Rule action. You would then choose the newly created business rule for the action by right clicking and going into settings.