How is the security of the connection guaranteed via DB access?

I currently have the following in use:

One Identity Manager on Demand 9.2
Jobserver onprem with the Starling Connect Client 9.2

As mentioned in the documentation, the job server is now recommended to always access the DB like https and the app server, but you need direct SQL access to the SQL Managed Instance for compilation. I now naturally assume that the connection is secure out of the box and that all communication is encrypted. I have read the following articles from Microsoft.

For me, however, the question now arises is the direct SQL connection encrypted and how is this technically guaranteed, has the client already integrated a certificate? Is everything encrypted during the exchange analogue to https or do I have to set something else here?