我有以下架构
CREATE TABLE years (
year_id INT NOT NULL AUTO_INCREMENT,
year_name_in_nums int NOT NULL,
year_name_in_text varchar(255) NOT NULL,
PRIMARY KEY (year_id)
)ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE classes (
class_id INT NOT NULL AUTO_INCREMENT,
class_name varchar(255) NOT NULL,
PRIMARY KEY (class_id)
)ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE students (
student_id INT NOT NULL AUTO_INCREMENT,
student_names varchar(255) NOT NULL,
student_telephone_number int NOT NULL,
PRIMARY KEY (student_id)
)ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE terms (
term_id INT NOT NULL AUTO_INCREMENT,
term_name_in_nums int NOT NULL,
term_name_in_text varchar(255) NOT NULL,
term_year int NOT NULL,
PRIMARY KEY (term_id),
FOREIGN KEY (term_year) REFERENCES years(year_id) ON DELETE CASCADE ON UPDATE CASCADE
)ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE class_students (
cs_id INT NOT NULL AUTO_INCREMENT,
cs_class_student int NOT NULL,
cs_class_id int NOT NULL,
cs_term_id int NOT NULL,
PRIMARY KEY (cs_id),
FOREIGN KEY (cs_class_student) REFERENCES students(student_id) ON DELETE CASCADE ON UPDATE CASCADE,
FOREIGN KEY (cs_class_id) REFERENCES classes(class_id) ON DELETE CASCADE ON UPDATE CASCADE,
FOREIGN KEY (cs_term_id) REFERENCES terms(term_id) ON DELETE CASCADE ON UPDATE CASCADE
)ENGINE=InnoDB DEFAULT CHARSET=utf8;
我想term_name_in_nums从条款表和year_name_in_nums年份表中显示
我以这种方式检索数据
(select term_name_in_nums,term_year from terms INNER JOIN class_students ON term_id=cs_term_id);
从上面看，term_year是一个 FOREIGN KEY (term_year)，其中 REFERENCES years(year_id)
我正在尝试这个
(select term_name_in_nums from terms INNER JOIN class_students ON term_id=cs_term_id)
LEFT JOIN
(select term_year from terms INNER JOIN class_students ON term_id=cs_term_id);
这给了我一个 sql 语法错误。我该如何解决这个问题？
编辑：数据
-- --------------------------------------------------------
-- Host: 127.0.0.1
-- Server version: 5.6.11 - MySQL Community Server (GPL)
-- Server OS: Win32
-- HeidiSQL Version: 8.0.0.4396
-- --------------------------------------------------------
/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET NAMES utf8 */;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
-- Dumping data for table algo.classes: ~10 rows (approximately)
/*!40000 ALTER TABLE `classes` DISABLE KEYS */;
INSERT IGNORE INTO `classes` (`class_id`, `class_name`) VALUES
(1, '1'),
(2, '2'),
(3, '3'),
(4, '4'),
(5, '5'),
(6, '6'),
(7, '7'),
(8, '8'),
(9, '9'),
(10, '10');
/*!40000 ALTER TABLE `classes` ENABLE KEYS */;
-- Dumping data for table algo.class_students: ~16 rows (approximately)
/*!40000 ALTER TABLE `class_students` DISABLE KEYS */;
INSERT IGNORE INTO `class_students` (`cs_id`, `cs_class_student`, `cs_class_id`, `cs_term_id`) VALUES
(1, 1, 1, 1),
(2, 1, 1, 1),
(3, 2, 1, 1),
(4, 3, 1, 1),
(5, 4, 1, 1),
(6, 5, 1, 1),
(7, 6, 1, 1),
(8, 7, 1, 1),
(9, 8, 1, 1),
(10, 9, 1, 1),
(11, 10, 1, 1),
(12, 11, 1, 1),
(13, 12, 1, 1),
(14, 13, 1, 1),
(15, 14, 1, 1),
(16, 15, 1, 1);
/*!40000 ALTER TABLE `class_students` ENABLE KEYS */;
-- Dumping data for table algo.examinations: ~3 rows (approximately)
/*!40000 ALTER TABLE `examinations` DISABLE KEYS */;
INSERT IGNORE INTO `examinations` (`examination_id`, `examination_name`, `examination_term_id`) VALUES
(1, 'start of term', 1),
(2, 'mid term', 1),
(3, 'end of term', 1);
/*!40000 ALTER TABLE `examinations` ENABLE KEYS */;
-- Dumping data for table algo.examination_data: ~0 rows (approximately)
/*!40000 ALTER TABLE `examination_data` DISABLE KEYS */;
/*!40000 ALTER TABLE `examination_data` ENABLE KEYS */;
-- Dumping data for table algo.students: ~20 rows (approximately)
/*!40000 ALTER TABLE `students` DISABLE KEYS */;
INSERT IGNORE INTO `students` (`student_id`, `student_names`, `student_telephone_number`) VALUES
(1, 'aa', 123456),
(2, 'bb', 5576899),
(3, '23050359165419520', 788399),
(4, '23050359165419521', 7892020),
(5, '23050359165419522', 33772),
(6, '23050359165419523', 86729),
(7, '23050359165419524', 526890),
(8, '23050359165419525', 444332),
(9, '23050359165419526', 937678),
(10, '23050359165419527', 44),
(11, '23050359165419528', 774),
(12, '23050359165419529', 2147483647),
(13, '23050359165419531', 2147483647),
(14, '23050359165419533', 2147483647),
(15, '23050359165419535', 353657674),
(16, '23050359165419536', 436),
(17, '23050359165419537', 5467),
(18, '23050359165419538', 565788),
(19, '23050359165419539', 548759898),
(20, '23050359165419540', 2443);
/*!40000 ALTER TABLE `students` ENABLE KEYS */;
-- Dumping data for table algo.terms: ~10 rows (approximately)
/*!40000 ALTER TABLE `terms` DISABLE KEYS */;
INSERT IGNORE INTO `terms` (`term_id`, `term_name_in_nums`, `term_name_in_text`, `term_year`) VALUES
(1, 1, 'term one', 1),
(2, 2, 'term two', 2),
(3, 3, 'term three', 3),
(4, 4, 'term four', 4),
(5, 5, 'term five', 5),
(6, 6, 'term six', 6),
(7, 7, 'term seven', 7),
(8, 8, 'term eight', 8),
(9, 9, 'term nine', 9),
(10, 10, 'term ten', 10);
/*!40000 ALTER TABLE `terms` ENABLE KEYS */;
-- Dumping data for table algo.years: ~15 rows (approximately)
/*!40000 ALTER TABLE `years` DISABLE KEYS */;
INSERT IGNORE INTO `years` (`year_id`, `year_name_in_nums`, `year_name_in_text`) VALUES
(1, 2000, '2000/2001'),
(2, 2001, '2001/2002'),
(3, 2002, '2002/2003'),
(4, 2003, '2003/2004'),
(5, 2004, '2004/2005'),
(6, 2005, '2005/2006'),
(7, 2006, '2006/2007'),
(8, 2007, '2007/2008'),
(9, 2008, '2008/2009'),
(10, 2009, '2009/2010'),
(11, 2010, '2010/2011'),
(12, 2011, '2011/2012'),
(13, 2012, '2012/2013'),
(14, 2013, '2013/2014'),
(15, 2014, '2014/2015');
/*!40000 ALTER TABLE `years` ENABLE KEYS */;
/*!40101 SET SQL_MODE=IFNULL(@OLD_SQL_MODE, '') */;
/*!40014 SET FOREIGN_KEY_CHECKS=IF(@OLD_FOREIGN_KEY_CHECKS IS NULL, 1, @OLD_FOREIGN_KEY_CHECKS) */;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;