Building custom field types for formula and roll-up summary calculations
In Chapter 2, Designing and Building a Data Model, we looked at custom fields in the Lightning Platform and at the selection of a data type when creating custom fields. In this section, we will look at two such data types in particular, namely, formula fields and roll-up summary fields.
Understanding formula calculations
Formulas can be created in a number of areas within the Lightning Platform and are used to generate a new value that is calculated or derived from values in other expressions or fields within the platform.
In this section, we will describe the features and functionality when creating formulas for custom fields, however, formulas can also be built within areas such as approval processes, assignment and auto-response rules, custom buttons and links, validation rules, and workflow rules.
We have already learned about assignment rules, auto-response rules, and custom buttons and links...