Question

我不确定我的查询是否正在执行问题。我要么弄错了问题，要么我对这个问题想要什么感到困惑。但是，从我提出的问题是找到所有会员ID，名字和姓氏，所有会员已经签出/或在“哈利波特”一书的过去签出。

以下是问题：

列出目前或过去借用图书馆中标题为“哈利波特”的所有图书的成员的memberID，名字和姓氏。如果任何此类书籍有多份副本，则该成员必须至少借用每本书籍的一份副本。

代码：

CREATE TABLE Book
    (bookID INT,
    ISBN INT,
    title varchar (60),
    author  varchar (20),
    publish_year INT,
    category varchar(20),
    PRIMARY KEY (bookID));  

CREATE TABLE Member
    (memberID INT,
    lastname varchar (20),
    firstname varchar (20),
    address varchar(20),
    phone_number INT,   
    limit_ INT,
    PRIMARY KEY (memberID));

CREATE TABLE CurrentLoan
    (memberID INT ,
    bookID INT,
    loan_date DATE,
    due_date DATE,
    PRIMARY KEY (memberID, bookID),
    FOREIGN KEY (memberID) REFERENCES Member(memberID),
    FOREIGN KEY (bookID) REFERENCES Book(bookID));

CREATE TABLE History
    (memberID INT,
    bookID INT,
    loan_date DATE,
    return_date DATE,
    PRIMARY KEY (memberID, bookID, loan_date),
    FOREIGN KEY (memberID) REFERENCES Member(memberID),
    FOREIGN KEY (bookID) REFERENCES Book(bookID));

INSERT INTO Book VALUES (10, 7771452369, 'XML and XQuery', 'Author Le', 2017, 'reference');
INSERT INTO Book VALUES (11, 8881245525, 'XQuery: The XML Query Language', 'Jack Se', 2017, 'reference');
INSERT INTO Book VALUES (12, 9991123546, 'Yellow Bird', 'Jake Red', 2014, 'reference');
INSERT INTO BOOK VALUES (13, 1212121212, 'The Giving Tree', 'Shel Silverstein', 1964, 'fiction');
INSERT INTO BOOK VALUES (14, 2121212121, 'Gone Fishing', 'Shel Silverstein', 1964, 'reference');
INSERT INTO BOOK VALUES (15, 1313131313, 'The Lazy Dog', 'Jake Red', 2016, 'childrens');
INSERT INTO BOOK VALUES (16, 3131313131, 'The Red Bird', 'Jake Red', 2016, 'childrens');
INSERT INTO BOOK VALUES (17, 1414141414, 'The Very Blue Boy', 'Ben Jen', 2006, 'fiction');
INSERT INTO Book VALUES (18, 1113312336, 'Harry Potter 1', 'J. K. Rowling', 2000, 'fiction');
Insert INTO Book VALUES (19, 1113331142, 'Harry Potter 1', 'J. K. Rowling', 2000, 'fiction');
INSERT INTO Book VALUES (20, 2221257787, 'The Real Harry Potter 2', 'J. K. Rowling', 2009, 'fiction');
INSERT INTO Book VALUES (21, 2221254896, 'The Fake Harry Potter 3', 'J. K. Rowling', 2010, 'fiction');
INSERT INTO Book VALUES (22, 2221254896, 'The Fake Harry Potter 3', 'J. K. Rowling', 2010, 'fiction');

INSERT INTO Member VALUES (001, 'Lee', 'Nancy', 'Brownlea Drive', 1254896325, 10);
INSERT INTO Member VALUES (002, 'Le', 'Ray', '10th Street', 1234561256, 2);
INSERT INTO Member VALUES (003, 'Kan', 'Charlie', '5th Street', 1234567236, 8);
INSERT INTO Member VALUES (004, 'Brown', 'Joe', 'Elm Street', 1234567845, 9);
INSERT INTO Member VALUES (005, 'Smith', 'John', '33 East', 1234567890, 3);
INSERT INTO Member VALUES (006, 'Kope', 'NON', '358 spence', 2145345625, 5);

INSERT INTO CurrentLoan VALUES (001, 10, '13-SEP-17', '14-NOV-17');
INSERT INTO CurrentLoan VALUES (001, 11, '13-SEP-17', '14-NOV-17');
INSERT INTO CurrentLoan VALUES (001, 18, '13-SEP-17', '14-NOV-17');
INSERT INTO CurrentLoan VALUES (001, 19, '13-SEP-17', '14-NOV-17');
INSERT INTO CurrentLoan VALUES (001, 21, '13-SEP-17', '14-NOV-17');
INSERT INTO CurrentLoan VALUES (001, 22, '13-SEP-17', '14-NOV-17');
INSERT INTO CurrentLoan VALUES (002, 11, '14-FEB-17', '12-MAR-17');
INSERT INTO CurrentLoan VALUES (003, 19, '12-OCT-17', '09-NOV-17');
INSERT INTO CurrentLoan VALUES (004, 13, '12-OCT-17', '09-NOV-17');
INSERT INTO CurrentLoan VALUES (004, 17, '12-OCT-17', '09-NOV-17');

INSERT INTO History VALUES (001, 15, '03-JAN-16', '25-MAY-16');
INSERT INTO History VALUES (001, 21, '03-JAN-16', '25-MAY-16');
INSERT INTO History VALUES (002, 21, '03-JAN-16', '25-MAY-16');
INSERT INTO History VALUES (002, 18, '03-JAN-16', '25-MAY-16');
INSERT INTO History VALUES (002, 15, '03-JAN-16', '25-MAY-16');
INSERT INTO History VALUES (002, 10, '03-JAN-16', '25-MAY-16');
INSERT INTO History VALUES (003, 10, '12-FEB-16', '05-MAY-16');
INSERT INTO History VALUES (004, 13, '12-JUN-16', '05-AUG-16');
COMMIT;

查询：

SELECT memberID, firstname, lastname
FROM (SELECT Member.memberID, firstname, lastname
      FROM Member, Book, CurrentLoan
      WHERE Member.memberID = CurrentLoan.memberID
      AND Book.bookID = CurrentLoan.bookID
      AND Book.title LIKE '%Harry Potter%')
UNION
SELECT memberID, firstname, lastname
FROM (SELECT Member.memberID, firstname, lastname
      FROM Member, Book, History
      WHERE Member.memberID = History.memberID
      AND Book.bookID = History.bookID
      AND Book.title LIKE '%Harry Potter%');

Answer 1

在提供正确答案方面，您的代码是正确的。但是，明确的JOIN语句更好，更不容易产生误解。另外，请查看oracle ...

的INSERT ALL结构

SELECT 
    Member.memberID AS MemberID
  , Member.firstname AS FirstName
  , Member.lastname AS LastName
FROM 
    Member 
        INNER JOIN 
            CurrentLoan ON CurrentLoan.memberID = Member.memberID
        INNER JOIN 
            Book ON CurrentLoan.bookID = Book.bookID 
            AND Book.title LIKE '%Harry Potter%'
UNION SELECT 
      Member.memberID
    , Member.firstname
    , Member.lastname
FROM 
    Member 
        INNER JOIN 
            History ON History.memberID = Member.memberID
        INNER JOIN 
            Book ON History.bookID = Book.bookID 
            AND Book.title LIKE '%Harry Potter%';

<强>更新

如果您只查找借用了所有三种不同HP图书的会员，则可以使用以下查询。请注意，使用现有数据，您根本不会得到任何结果。将计数更改为2，以查找已阅读该系列中至少2本图书的成员。

SELECT 
      MemberID
    , FirstName
    , LastName
FROM (
    SELECT 
          m.memberID AS MemberID
        , m.firstname AS FirstName
        , m.lastname AS LastName
        , b.Title AS BookTitle
    FROM 
        Member m 
            INNER JOIN CurrentLoan c ON c.memberID = m.memberID
            INNER JOIN Book b ON c.bookID = b.bookID 
                AND b.title LIKE '%Harry Potter%'
    UNION SELECT 
          m.memberID
        , m.firstname
        , m.lastname
        , b.Title
    FROM 
        Member m 
            INNER JOIN History h ON h.memberID = m.memberID
            INNER JOIN Book b ON h.bookID = b.bookID 
                AND b.title LIKE '%Harry Potter%'
) ResultSet
GROUP BY MemberID, FirstName, LastName
HAVING COUNT(DISTINCT BookTitle) = 3;

不确定我的查询是否正在做它应该做的事情

1 个答案: