It is not hard to isolate and stub a database the problem is you will not catch a lot of errors, e.g. writing a 40 char string into a VCHAR(10), DateTime conver

It is not hard to isolate and stub a database the problem is you will not catch a lot of errors, e.g. writing a 40 char string into a VCHAR(10), DateTime conversations, ... In Ruby on Rails it is quite common to use a real database in the unit tests. Even before containers came out and it is still fast (yes, less than 1 second). In rails you use the same database instance for all the tests, so you do not have spin up a database instance for every case. Instead you use a database cleaner. There also exists a JS implementation: https://github.com/khaiql/dbcleaner https://github.com/khaiql/dbcleaner