{"db": "library", "question": "一共有多少本书？", "sql": "SELECT COUNT(*) FROM books"}
{"db": "library", "question": "所有的书都是哪些作者写的？帮我列一下不重复的作者", "sql": "SELECT DISTINCT author FROM books WHERE author IS NOT NULL"}
{"db": "library", "question": "价格超过 50 块的书都有哪些？", "sql": "SELECT title FROM books WHERE price > 50"}
{"db": "library", "question": "2020 年以后出版的书，按出版年份从新到旧排一下，同一年的按书名排", "sql": "SELECT title FROM books WHERE publish_year > 2020 ORDER BY publish_year DESC, title"}
{"db": "library", "question": "每个分类下有多少本书？", "sql": "SELECT category, COUNT(*) AS book_count FROM books GROUP BY category"}
{"db": "library", "question": "书的平均价格是多少？", "sql": "SELECT AVG(price) FROM books"}
{"db": "library", "question": "藏书量最多的前五个分类是哪些？", "sql": "SELECT category FROM books GROUP BY category ORDER BY SUM(total_copies) DESC LIMIT 5"}
{"db": "library", "question": "女性读者一共有几位？", "sql": "SELECT COUNT(*) FROM readers WHERE gender = '女'"}
{"db": "library", "question": "注册日期在 2023 年之后的读者都叫什么名字？", "sql": "SELECT name FROM readers WHERE date(register_date) > '2023-12-31'"}
{"db": "library", "question": "每种读者类型各有多少人？", "sql": "SELECT reader_type, COUNT(*) AS cnt FROM readers GROUP BY reader_type"}
{"db": "library", "question": "借出去还没还的书有哪些？把书名和读者名字都列出来", "sql": "SELECT b.title, r.name FROM borrows br JOIN books b ON br.book_id = b.book_id JOIN readers r ON br.reader_id = r.reader_id WHERE br.return_date IS NULL"}
{"db": "library", "question": "一共借出过多少次，按书统计一下，取借得最多的前三个，次数一样的按书的编号从小到大取", "sql": "SELECT b.title, COUNT(*) AS times FROM borrows br JOIN books b ON br.book_id = b.book_id GROUP BY br.book_id ORDER BY times DESC, br.book_id LIMIT 3"}
{"db": "library", "question": "有罚款记录的借阅，罚款总额是多少？", "sql": "SELECT SUM(fine) FROM borrows WHERE fine > 0"}
{"db": "library", "question": "哪位读者借的书最多？", "sql": "SELECT r.name FROM borrows br JOIN readers r ON br.reader_id = r.reader_id GROUP BY br.reader_id ORDER BY COUNT(*) DESC LIMIT 1"}
{"db": "library", "question": "上个月借出去的书都是哪些？列一下借阅日期", "sql": "SELECT b.title, br.borrow_date FROM borrows br JOIN books b ON br.book_id = b.book_id WHERE strftime('%Y-%m', br.borrow_date) = strftime('%Y-%m', 'now', '-1 month')"}
{"db": "library", "question": "从来没有被借过的书有哪些？", "sql": "SELECT title FROM books WHERE book_id NOT IN (SELECT book_id FROM borrows WHERE book_id IS NOT NULL)"}
{"db": "library", "question": "员工里工资最高的前三位是谁？", "sql": "SELECT name FROM staff ORDER BY salary DESC LIMIT 3"}
{"db": "library", "question": "每个岗位有多少员工，平均工资是多少？", "sql": "SELECT position, COUNT(*) AS cnt, AVG(salary) AS avg_salary FROM staff GROUP BY position"}
{"db": "library", "question": "把每个读者的借阅次数和罚款总额一起统计出来，包括没借过书的读者", "sql": "SELECT r.name, COUNT(br.borrow_id) AS borrow_count, COALESCE(SUM(br.fine), 0) AS total_fine FROM readers r LEFT JOIN borrows br ON r.reader_id = br.reader_id GROUP BY r.reader_id"}
{"db": "library", "question": "借过的书里，出版社年份早于 2000 年的书名和借阅日期", "sql": "SELECT b.title, br.borrow_date FROM borrows br JOIN books b ON br.book_id = b.book_id WHERE b.publish_year < 2000"}
{"db": "library", "question": "把所有价格超过50块钱的书列出来，按价格从高到低排。", "sql": "SELECT title FROM books WHERE price > 50 ORDER BY price DESC"}
{"db": "library", "question": "图书馆里一共收录了多少种书？", "sql": "SELECT COUNT(*) FROM books"}
{"db": "library", "question": "有哪些读者是女生？只要名字和注册日期。", "sql": "SELECT name, register_date FROM readers WHERE gender = '女'"}
{"db": "library", "question": "每个类别各有多少本书？", "sql": "SELECT category, COUNT(*) AS book_count FROM books GROUP BY category"}
{"db": "library", "question": "2020年以后出版的书里，平均价格是多少？", "sql": "SELECT AVG(price) FROM books WHERE publish_year > 2020"}
{"db": "library", "question": "借出去还没还的记录有哪些？把书名和读者名字都带上。", "sql": "SELECT b.title, r.name FROM borrows br JOIN books b ON br.book_id = b.book_id JOIN readers r ON br.reader_id = r.reader_id WHERE br.return_date IS NULL"}
{"db": "library", "question": "罚款金额最高的前五条借阅记录，显示读者姓名和罚款。", "sql": "SELECT r.name, br.fine FROM borrows br JOIN readers r ON br.reader_id = r.reader_id WHERE br.fine IS NOT NULL ORDER BY br.fine DESC LIMIT 5"}
{"db": "library", "question": "每位读者总共借过几次书？按次数从多到少排，次数一样的按读者ID从小到大。", "sql": "SELECT r.name, COUNT(*) AS times FROM borrows br JOIN readers r ON br.reader_id = r.reader_id GROUP BY br.reader_id ORDER BY times DESC, br.reader_id"}
{"db": "library", "question": "哪个作者的藏书总册数最多？", "sql": "SELECT author FROM books GROUP BY author ORDER BY SUM(total_copies) DESC LIMIT 1"}
{"db": "library", "question": "查一下今年的借阅记录有多少条。", "sql": "SELECT COUNT(*) FROM borrows WHERE strftime('%Y', borrow_date) = strftime('%Y', 'now')"}
{"db": "library", "question": "借书超过3次的读者有哪些？只要名字。", "sql": "SELECT r.name FROM borrows br JOIN readers r ON br.reader_id = r.reader_id GROUP BY br.reader_id HAVING COUNT(*) > 3"}
{"db": "library", "question": "列出从来没有被借过的书。", "sql": "SELECT title FROM books WHERE book_id NOT IN (SELECT book_id FROM borrows)"}
{"db": "library", "question": "各个岗位的员工平均工资是多少？", "sql": "SELECT position, AVG(salary) FROM staff GROUP BY position"}
{"db": "library", "question": "逾期还没还的书有哪些？也就是过了应还日期还是空的，同一本书只列一次。", "sql": "SELECT DISTINCT b.title FROM borrows br JOIN books b ON br.book_id = b.book_id WHERE br.return_date IS NULL AND date(br.due_date) < date('now')"}
{"db": "library", "question": "每个类别的书里，最贵的那本多少钱？", "sql": "SELECT category, MAX(price) FROM books GROUP BY category"}
{"db": "library", "question": "注册时间最晚的5位读者是谁？注册日期相同的按读者ID从小到大取。", "sql": "SELECT name FROM readers ORDER BY register_date DESC, reader_id LIMIT 5"}
{"db": "library", "question": "最受欢迎的前三本书是哪些？按被借次数算，次数一样的按书的编号从小到大取。", "sql": "SELECT b.title FROM borrows br JOIN books b ON br.book_id = b.book_id GROUP BY br.book_id ORDER BY COUNT(*) DESC, br.book_id LIMIT 3"}
{"db": "library", "question": "工资比全馆平均工资高的员工有哪些？", "sql": "SELECT name FROM staff WHERE salary > (SELECT AVG(salary) FROM staff)"}
{"db": "library", "question": "哪一年出版的书最多？并列的年份都列出来。", "sql": "WITH c AS (SELECT publish_year, COUNT(*) AS cnt FROM books GROUP BY publish_year) SELECT publish_year FROM c WHERE cnt = (SELECT MAX(cnt) FROM c)"}
{"db": "library", "question": "上个月借书的记录，把读者名字和书名都列出来。", "sql": "SELECT r.name, b.title FROM borrows br JOIN readers r ON br.reader_id = r.reader_id JOIN books b ON br.book_id = b.book_id WHERE strftime('%Y-%m', br.borrow_date) = strftime('%Y-%m', 'now', '-1 month')"}