CREATE TABLE tblTeenagers
([Nickname] varchar(20), [Bdate] date, [Gender] varchar(20), [Age] int);
INSERT INTO tblTeenagers
([Nickname], [Bdate], [Gender], [Age])
VALUES
('Lucas', '2002-03-30', 1, 18),
('Petra', '2001-07-22', 2, 19),
('JC', '2002-01-25', 1, 18),
('Mateo', '2000-02-14', 1, NULL),
('Pablo', '2003-08-24', 1, 17),
('Mar', '2001-07-25', 2, 19),
('Belle', '2000-01-01', NULL, 20),
('Zai', '2000-04-09', NULL, 20);
CREATE TABLE tblTeenGender
([GenderID] int, [Description] varchar(20));
INSERT INTO tblTeenGender
([GenderID], [Description])
VALUES
(1, 'Male'),
(2, 'Female');
SELECT * FROM tblTEENAGERS;
SELECT * FROM tblTeenGender;
SELECT NickName, Gender, Age FROM tblTEENAGERS
UNION
SELECT Description, NULL, NULL FROM tblTeenGender;
SELECT t.[NickName], t.[Age], g.[Description]
FROM tblTEENAGERS t
INNER JOIN tblTeenGender g ON t.[Gender] = g.[GenderID];
SELECT t.[NickName], t.[Age], g.[Description]
FROM tblTeenGender g
RIGHT JOIN tblTEENAGERS t ON t.[Gender] = g.[GenderID];
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