CREATE TABLE tblTEENAGERS
([Nickname] varchar(20), [BirthDate] date, [Gender] int, [Age] int);
INSERT INTO tblTEENAGERS
([Nickname], [BirthDate], [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 tblTEENAGERS t
RIGHT JOIN tblTEENGENDER G ON t. [Gender] = g.[GenderID];
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