[Mikhail_Edoshin]

It solves a hard problem. For example, it completely insulates the sender from the fact that his transaction is just one among many others.

[jhgb]

No, database servers solve that problem. That the unnecessarily COBOL-like SQL ended up being the primary interface to them is simply an unfortunate accident of history.

[Mikhail_Edoshin]

There have to be some limitations on the language for this to work. For example, there must be no way to specify a neverending loop or to lock something and forget to unlock, an so on.