OK - how many practical declarative goal-based languages have been successful in the past 50 years? Only option I can think of till now is SQL. Maybe there were

OK - how many practical declarative goal-based languages have been successful in the past 50 years? Only option I can think of till now is SQL. Maybe there were some Operational Research optimization stuff as well. All of these were quite limited in terms of the kinds of goals we could specify, and the range of impacts they could have on the world. The possibility of pure goal-oriented systems are at an inception now. So it's a totally different game, different mechanisms, and so on.