Using formula queries in custom data rules and custom role permissions

This article contains examples and guidelines for using formula queries in custom data rules and custom role permissions

Custom data rules

Custom data rules allow you to validate data. Using formula queries, you can do things like:

• Prevent duplicates in a table
• Stop users from adding new records, based on fields in other tables

We'll cover each of these examples in more depth.

Example: Prevent duplicates

You could use a custom data rule to prevent potential duplicates on a table.

If(Size(GetRecords("{6.EX.'"&[Customer Name]&"'}AND{7.EX.'"&[Region]&"'}")) > 1, "This customer already has an account entry for this region. Please choose a different region for this customer or enter a new customer name.")

• This formula uses the Size function to count how many records have the same Customer Name and Region as the current record.
• If that number is greater than 1, that means a record already exists with the same customer name and region
• The record will not be saved and the user will see the message: "This customer already has an account entry for this region. Please choose a different region for this customer or enter a new customer name."

Example: Stop users from adding records if criteria in other tables are not met

Assume you have two unrelated tables, Projects and Invoices. You don’t want to allow a new project to be started while there are outstanding invoices.

You could add a custom data rule on the Projects table, similar to this one:

If(Size(GetRecords("{7.XEX.'Complete'}", [_DBID_INVOICES])) > 0, "You must complete all invoices before starting a new project")

• This formula uses the Size function to count how many records do not have the value “Complete” populating field ID 7.
• If that number is greater than 0, that means there is a record not marked “Complete”
• The user will see the message: “You must complete all invoices before starting a new project.”

Custom role permissions

• If adding formula queries to custom role permission formulas, it is best if they reference a different table than the one they calculate on
• Using a formula query that references its own table may cause unexpected behavior 
• This is because a change on one record could invalidate a related record