It's mostly a familiarity and education problem, as well as the fact MySQL didn't have good support for this. Developers are exposed to procedural programming l

It's mostly a familiarity and education problem, as well as the fact MySQL didn't have good support for this. Developers are exposed to procedural programming languages at university, but seldom to databases, let alone stored procedures. Unit tests can be written in SQL or PL/PGSQL and will typically run much faster than a CI pipeline.