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我该如何去写这个查询？我正在考虑使用count，inner join和group by。计数的书和历史
CurrentLoan是最近出版的书籍退房和历史是过去的书籍，是退房。
目标：对于每个成员（成员ID，姓氏和名字）列出成员当前签出的书籍数量以及成员过去签出的书籍数量。如果一个成员多次签出同一本书，它将被多次计数。如果成员没有书退房它应该算作0
代码：
CREATE TABLE Book
(bookID INT,
ISBN INT,
title varchar (30),
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, 'childrens');
INSERT INTO Book VALUES (15, 5552314569, 'Green Apple', 'Theo Brown', 1978, 'childrens');
INSERT INTO Book VALUES (16, 6664581631, 'Red Bean', 'Khang Nk', 2017, 'fiction');
INSERT INTO Book VALUES (17, 7771452369, 'XML and XQuery', 'Author Le', 2017, 'non-fiction');
INSERT INTO Book VALUES (18, 8881245525, 'The Dark Room', 'Jack Se', 2017, 'fiction');
INSERT INTO Book VALUES (19, 9991123546, 'Yellow Bird', 'Jake Red', 2014, 'reference');
INSERT INTO Book VALUES (20, 1122112356, 'XQuery: The XML Query Language', 'Heart Le', 2002, 'fiction');
INSERT INTO BOOK VALUES (21, 1212121212, 'The Giving Tree', 'Shel Silverstein', 1964, 'fiction');
INSERT INTO BOOK VALUES (22, 2121212121, 'Gone Fishing', 'Shel Silverstein', 1964, 'reference');
INSERT INTO BOOK VALUES (23, 1313131313, 'The Lazy Dog', 'Jake Red', 2016, 'childrens');
INSERT INTO BOOK VALUES (24, 3131313131, 'The Red Bird', 'Jake Red', 2016, 'childrens');
INSERT INTO BOOK VALUES (25, 1414141414, 'The Very Blue Boy', 'Ben Jen', 2006, '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, 'Khang', 'Nkaujyi', '358 Spencer', 2145345625, 5);
INSERT INTO Member VALUES (007, 'Jones', 'David', '4th Street', 14812365789, 10);
INSERT INTO Member values (008, 'Lee', 'Tou', 'Lee Street', 2145632562, 1);
INSERT INTO Member values (009, 'Jones', 'John', '1st Street', 0124789541, 7);
INSERT INTO CurrentLoan VALUES (006, 17, '14-FEB-17', '12-MAR-17');
INSERT INTO CurrentLoan VALUES (004, 17, '12-OCT-17', '09-NOV-17');
INSERT INTO CurrentLoan VALUES (004, 20, '12-OCT-17', '09-NOV-17');
INSERT INTO CurrentLoan VALUES (005, 18, '13-APR-17', '12-MAY-17');
INSERT INTO CurrentLoan VALUES (007, 25, '02-OCT-17', '25-DEC-17');
INSERT INTO CurrentLoan VALUES (008, 15, '03-MAY-17', '08-AUG-17');
INSERT INTO CurrentLoan VALUES (008, 12, '03-MAY-17', '08-AUG-17');
INSERT INTO CurrentLoan VALUES (009, 12, '02-OCT-17', '23-NOV-17');
INSERT INTO CurrentLoan VALUES (009, 14, '23-JUN-17', '24-OCT-17');
INSERT INTO History VALUES (008, 12, '03-JAN-16', '25-MAY-16');
INSERT INTO History VALUES (008, 15, '03-JAN-16', '25-MAY-16');
INSERT INTO History VALUES (009, 20, '12-FEB-16', '05-MAY-16');
INSERT INTO History VALUES (009, 15, '12-JUN-16', '05-AUG-16');
INSERT INTO History VALUES (006, 20, '14-MAY-16', '04-DEC-16');
INSERT INTO History VALUES (007, 12, '02-OCT-16', '25-DEC-16');
COMMIT;
这是我到目前为止，查询：
这就是我想要的输出是：
memberID lastname firstname numberofbooks
1 Lee Nancy 0
2 Le Ray 0
3 Kan Charlie 0
4 Brown Joe 2
5 Smith John 1
6 Khang Nkaujyi 2
7 Jones David 2
8 Lee Tou 4
9 Jones John 4
只是到目前，其中的历史（过去）的作品？它应该能够获得当前和历史成员的书籍总数。 – tubvajlis
善良，为什么不尝试自己的东西，更好的学习方式，但在一会儿，我会添加缺少的加入，并计数 –
我一直在做这个问题近4个小时，无法得到它。 – tubvajlis