它說我沒有選擇行？

Question

這是說我沒有選擇行。

這就是問題： 找到過去或現在從未借過任何書籍的成員的會員ID，姓氏和名字。

這是模式，主鍵是粗體。

書（BOOKID，ISBN，書名，作者，出版年，類別）

會員（MEMBERID，姓氏，名字，地址，電話號碼，限制）

CurrentLoan（ MEMBERID，BOOKID，貸款日期，到期日期）

歷史（MEMBERID，bookID，loan-date，return-date）

會員可以從圖書館借書。他們可以借閱的書籍數量受到會員關係「限制」字段的限制（對於不同的會員可能會有所不同）。一本書的類別包括小說，非小說，兒童和參考。 CurrentLoan表格表示當前檢出的書籍信息。當書籍返回到圖書館時，記錄將從CurrentLoad關係中刪除，並將插入到與返回日期相關的歷史記錄關係中。圖書館可能有同一本書的多個副本，在這種情況下，每個副本都有自己的bookID，但所有副本都共享相同的ISBN。

這是我的代碼：

CREATE TABLE Book 
    (bookID INT, 
    ISBN INT, 
    title varchar (25), 
    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, 1113312336, 'The Dog', 'Jack Crow', 1990, 'fiction'); 
INSERT INTO Book VALUES (12, 2221254896, 'Worms', 'Jim Kan', 2013, 'childrens'); 
INSERT INTO Book VALUES (13, 3332546987, 'Crow', 'Jan Flo', 2000, 'fiction'); 
INSERT INTO Book VALUES (14, 4443456215, 'Big Dog', 'Lan Big', 1993, 'children'); 
INSERT INTO Book VALUES (15, 5552314569, 'Green Apple', 'Theo Brown', 1978, 'children'); 
INSERT INTO Book VALUES (16, 6664581631, 'Red Bean', 'Khang Nk', 2017, 'fiction'); 
INSERT INTO Book VALUES (17, 7771452369, 'XML and XQuery Knowledge', 'Author Le', 2017, 'non-fiction'); 
INSERT INTO Book VALUES (18, 8881245525, 'The Dark Room', 'Jack Se', 2017, 'fiction'); 
INSERT INTO Book VALUES (19, 9991123546, 'Lonely Mens', 'Geen Brown', 2014, 'refrence'); 
INSERT INTO Book VALUES (20, 1122112356, 'XML or XQuery', 'Heart Le', 2002, 'fiction'); 

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

INSERT INTO CurrentLoan VALUES (005, 10, '13-SEP-17', '14-NOV-17'); 
INSERT INTO CurrentLoan VALUES (005, 19, '13-JAN-17', '15-NOV-17'); 
INSERT INTO CurrentLoan VALUES (003, 16, '14-FEB-17', '12-MAR-17'); 
INSERT INTO CurrentLoan VALUES (004, 15, '12-OCT-17', '09-NOV-17'); 
INSERT INTO CurrentLoan VALUES (005, 18, '13-APR-17', '12-MAY-17'); 

INSERT INTO History VALUES (001, 10, '14-Jan-17', '04-OCT-17'); 
INSERT INTO History VALUES (002, 19, '12-Jan-17', '04-NOV-17'); 
INSERT INTO History VALUES (003, 13, '14-APR-17', '08-OCT-17'); 
INSERT INTO History VALUES (005, 20, '14-MAY-17', '04-DEC-17'); 

我的查詢是：

SELECT Member.memberID, lastname, firstname 
    FROM Member MINUS(
        SELECT Member.memberID, lastname, firstname 
        FROM Member, CurrentLoan 
        WHERE Member.memberID = CurrentLoan.memberID 
        UNION 
        SELECT Member.memberID, lastname, firstname 
        FROM Member, History 
        WHERE Member.memberID = History.memberID); 

Answer 1

有幾個方法可以做到這一點：

您可以使用反連接，如：

SELECT m.MEMBERID, 
     m.LASTNAME, 
     m.FIRSTNAME 
    FROM MEMBERS m 
    WHERE m.MEMBERID NOT IN (SELECT DISTINCT MEMBERID 
          FROM CURRENTLOAN 
          UNION ALL 
          SELECT DISTINCT MEMBERID 
          FROM HISTORY); 

另一種方式（和我的首選方法）做你想要的是：

SELECT DISTINCT m.MEMBERID, 
       m.LASTNAME, 
       m.FIRSTNAME 
    FROM MEMBERS m 
    LEFT OUTER JOIN (SELECT DISTINCT MEMBERID 
        FROM (SELECT MEMBERID 
          FROM CURRENTLOAN 
          UNION ALL 
          SELECT MEMBERID 
          FROM HISTORY)) u 
    ON u.MEMBERID = m.MEMBERID 
    WHERE u.MEMBERID IS NULL; 

然而，鑑於你已經證明這個查詢，以及您的原始查詢的數據，應該返回零行。 SQLFiddle here

請注意，如果您註釋掉當前貸款成員004，那麼「喬布朗」返回SQLFiddle here

好運。