-- create a table
CREATE TABLE students (
  id INTEGER PRIMARY KEY,
  name TEXT NOT NULL,
  gender TEXT NOT NULL,
    edad INTEGER NOT NULL,
    nacionalidad TEXT NOT NULL
);
-- insert some values
INSERT INTO students VALUES (1, 'Tomás Pérez', 'M', 28, 'argentina');
INSERT INTO students VALUES (2, 'Mayra Celiz', 'F', 46, 'argentina');
INSERT INTO students VALUES (3, 'Kyra Figueroa', 'F', 22, 'argentina');
    INSERT INTO students VALUES (4, 'Francisco Azurmendi', 'M', 17, 'colombiano');
-- fetch some values
SELECT * FROM students WHERE gender = 'F' AND edad > 21;