Question

我正在尝试从我的Album和ArtistBand表中进行选择，并按字母顺序显示Name和Bandname。当尝试使用下面的select语句时，它会显示每个乐队的所有专辑。任何帮助都将受到学校的赞赏。

CREATE TABLE ArtistBand 
(
    ArtistID INT AUTO_INCREMENT PRIMARY KEY,
    BandName VARCHAR(255) NOT NULL,
    NameOfMembers VARCHAR(255),
    NumberOfMembers INT
);

CREATE TABLE Genre
(
    GenreID INT AUTO_INCREMENT PRIMARY KEY,
    GenreType VARCHAR(255) NOT NULL
);

CREATE TABLE Album 
(
    AlbumID INT AUTO_INCREMENT PRIMARY KEY,
    Name VARCHAR (255) NOT NULL,
    ReleaseDate DATE NOT NULL,
    Producers VARCHAR (255),
    ArtistID INT,
    GenreID INT,
    FOREIGN KEY(ArtistID) REFERENCES ArtistBand(ArtistID),
    FOREIGN KEY (GenreID) REFERENCES Genre (GenreID)
);

CREATE TABLE LookUp
(
    AlbumID INT,
    GenreID INT,
    FOREIGN KEY (AlbumID) REFERENCES Album (AlbumID),
    FOREIGN KEY (GenreID) REFERENCES Genre (GenreID)
);

INSERT INTO ArtistBand 
VALUES
    (NULL,'ACDC','BrianJohnson',4),
    (NULL,'Metallica','JamesHeitfield',4),
    (NULL,'TheBeatles','JohnLennon',4),
    (NULL,'JayZ','ShawnCarter',1),
    (NULL,'DangerMouse','BrianBurton',1);

INSERT INTO Album 
VALUES
    (NULL,'BackInBlack','1980-01-01',NULL,NULL,NULL),
    (NULL,'TheBlackAlbum','1991-01-01',NULL,NULL,NULL),
    (NULL,'WhiteAlbum','1968-01-01',NULL,NULL,NULL),
    (NULL,'TheBlackAlbum','2003-01-01',NULL,NULL,NULL),
    (NULL,'TheGreyAlbum','2004-01-01',NULL,NULL,NULL);

INSERT INTO Genre 
VALUES
    (NULL,'HeavyMetal'),
    (NULL,'HeavyMetal'),
    (NULL,'Pop'),
    (NULL,'HipHop'),
    (NULL,'HipHop');

SELECT   
    ArtistBand.BandName, Album.Name
FROM     
    ArtistBand
JOIN     
    Album 
ORDER BY 
    ArtistBand.BandName;

Answer 1

您需要在联接中添加条件，ArtistID在两个表中应该相同。因此，您的查询将如下所示：

SELECT   ArtistBand.BandName, Album.Name
FROM     ArtistBand
JOIN     Album ON ArtistBand.ArtistID = Album.ArtistID
ORDER BY ArtistBand.BandName;

SQL SELECT来自两个表内部联接

1 个答案: