text: SELECT 42.3;
  SELECT 42.3+5;
  SELECT 42.3*5;
  SELECT 2^8;
  SELECT 2^16;
  SELECT 9%2;
  SELECT 999%50;
  SELECT 999/50;
  SELECT 999/50 AS "result", 999%50 AS "remainder";
  -- round
  SELECT ROUND(42.3, 2);
  SELECT ROUND(42.3, 0);
  SELECT ROUND(42.3);
  SELECT ROUND(42.9);
  SELECT ROUND(42.9, 4);
  -- absolute value
  SELECT @ -42.3;