Not using FK constraints is my company's untold rule. FK constraints are used only when designing ERD and not used when creating tables.

According to my senior, in real practice, those are very time consuming obstacles when we are dealing with urgent issues. He says when we need to use INSERT/UPDATE/DELETE statements immediately, the constraints block those statements to be executed and writing statements while keeping the constraints is time consuming too. I even heard many other companies are doing this.

While I kinda understand the struggles, I'm not sure if this is a good way since it's quite opposite to my understanding to DB. This company is my first job too, so I don't know how other companies dealing with this.

In practical way, what is your opinion about this? Can this be justified? Are there better ways? How other companies are doing about this matters?

UPDATE: It seems it is a quite common approach for South Korean companies. I asked a few other seniors who worked for other companies, and most of them are saying they all doing like this. And even one of them worked for a financial company! Interesting...