Guide
You can setup automatic Relations based on some basic matching rules. It is mostly needed for integrations, but there are other cases as well.
How to set an automatic relation
Create a new Relation field and setup a new relation.
Click Automatically link switcher.
Specify matching fields. For example, you have City and Country databases. In a City database you have a text field CAbbr with Country abbreviation, and in Country database you have a field Abbr with Country abbreviation. In this case select CAbbr and Abbr fields for correspondent database to create a matching rule.
You might want to create a new formula fields to extract the required information to be matched, and then use this formula field in the matching rule.
Example
Below we automatically link Pull Requests from GitHub to User Stories in Fibery.
https://www.loom.com/share/f9921158275a4375be76937b41476208
Here is the formula that extracts user story id from fibery/us#123 some name
If(StartsWith(Name,"fibery/us#"),Trim(ReplaceRegex(Name,"fibery\/us#(\d+).+"," \1 ")),"")
And here is the rule: