Comment by moonchild

IMO better would be a database interface that acts as a normal programming language, treating tables as arrays of records. Compare:

  how many teachers older than 30
  teachers.filter(*.age > 30).len

Same length, but the second one has a degree of precision that the first lacks. (Though they might diverge somewhat as the complexity of queries grows, I suspect programming languages would do better as they have better facilities for symbolic manipulation.) Note also that the second example (and your SQL example) had to specify the table's name, while the natural language one did not—another mark against the natural language solution.