Requirements for an imperative language amenable to sql-like optimizations

[mildred]

By the way, I was thinking lately that I'd like a database engine where I could 
specifically tell how to fetch the data and what index to use, the compiler 
yelling at me if I try something impossible, rather than relying on declarative 
SQL, and depending on guesses from the query optimizer for performance, and 
suffering when it guesses wrong from what I thought. Does such a system exists ?