i occasionally have to work with a big application which is essentially written 100% in sql. you simply can't easily change parts without testing the whole thing from start to finish because automated testing at a granular level is horrible. and sql does not lend itself to encapsulation, it does everything to make it hard to break stuff down to manageable pieces

and in sql everything you do is just so complicated, tons of boilerplate stuff you would not have in a real programming language. it's called "query language" after all, not "programming language". so don't use it for that