SELECT * FROM "izotopy"
  LIMIT 10;

SELECT A, Z, element FROM "izotopy"
  LIMIT 10;

SELECT A, Z, element FROM "izotopy"
  WHERE element = "H";

SELECT A, Z, element FROM "izotopy"
  WHERE A = 10;

SELECT A, Z, element FROM "izotopy"
  WHERE A = 100;

SELECT count(*) FROM "izotopy"
  WHERE A = 100;

SELECT * FROM "izotopy"
  WHERE T12 = "STABLE";

SELECT count(*) FROM "izotopy"
  WHERE T12 = "STABLE";

SELECT * FROM "izotopy"
  WHERE T12 = "STABLE" AND A < 100;

SELECT count(*) FROM "izotopy"
  WHERE T12 = "STABLE" AND A < 100;