如何从 mysql 中的所有六个表中收集数据

Question

我试过内部连接，但我无法弄清楚我在做什么错。如何查询蓝框内全部6个table的数据

studentprofile table 是蓝色区域中其他 5 table 之间的 link。

我运行这个查询，这显示了我所有的数据。

select * from users, roles_assigned,studentprofile,schoolwithusers;

我面临的问题是我只需要为学生用户、学校名称和学生资料过滤数据请帮忙。这是我的 sql 代码。

    
--
-- Database: `onlinemarksheets`
--

-- --------------------------------------------------------

--
-- Table structure for table `exams`
--

CREATE TABLE `exams` (
  `id` int(11) NOT NULL,
  `examtye_id` int(11) DEFAULT NULL,
  `schooluser_id` int(11) DEFAULT NULL,
  `duration_to` date DEFAULT NULL,
  `duration_from` date DEFAULT NULL,
  `year` date DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- --------------------------------------------------------

--
-- Table structure for table `examtype`
--

CREATE TABLE `examtype` (
  `id` int(11) NOT NULL,
  `type` enum('Mid-Term','Half-yearly','Yearly') DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

--
-- Dumping data for table `examtype`
--

INSERT INTO `examtype` (`id`, `type`) VALUES
(1, 'Mid-Term'),
(2, 'Half-yearly'),
(3, 'Yearly');

-- --------------------------------------------------------

--
-- Table structure for table `marks`
--

CREATE TABLE `marks` (
  `id` int(11) NOT NULL,
  `exam_id` int(11) DEFAULT NULL,
  `name` varchar(45) DEFAULT NULL,
  `marks_obtained` int(11) DEFAULT NULL,
  `marks_total` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- --------------------------------------------------------

--
-- Table structure for table `roles`
--

CREATE TABLE `roles` (
  `id` int(11) NOT NULL,
  `type` enum('Admin','Teacher','Student') DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

--
-- Dumping data for table `roles`
--

INSERT INTO `roles` (`id`, `type`) VALUES
(1, 'Admin'),
(2, 'Teacher'),
(3, 'Student');

-- --------------------------------------------------------

--
-- Table structure for table `roles_assigned`
--

CREATE TABLE `roles_assigned` (
  `id` int(11) NOT NULL,
  `role_id` int(11) DEFAULT NULL,
  `user_id` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

--
-- Dumping data for table `roles_assigned`
--

INSERT INTO `roles_assigned` (`id`, `role_id`, `user_id`) VALUES
(1, 1, 1),
(2, 2, 2),
(3, 3, 3),
(4, 3, 4),
(5, 3, 5),
(6, 3, 6),
(7, 1, 1),
(8, 2, 2),
(9, 3, 3),
(10, 3, 4),
(11, 3, 5),
(12, 3, 6);

-- --------------------------------------------------------

--
-- Table structure for table `schools`
--

CREATE TABLE `schools` (
  `id` int(11) NOT NULL,
  `schoolname` varchar(45) DEFAULT NULL,
  `school_email` varchar(45) DEFAULT NULL,
  `school_phone` varchar(45) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

--
-- Dumping data for table `schools`
--

INSERT INTO `schools` (`id`, `schoolname`, `school_email`, `school_phone`) VALUES
(1, 'D.A.V Public school', 'info@davschool.com', '789456123'),
(2, 'saraswati Public school', 'info@saraswatischool.com', '9998887774'),
(3, 'S.G.R.R Public School', 'Info@sgrr.com', '54245645125'),
(4, 'Sun Valley Public', 'info@sunvalley.com', '23423423424'),
(5, 'Marshal Public school', 'info@marshalschool.com', '23482728347');

-- --------------------------------------------------------

--
-- Table structure for table `schoolwithusers`
--

CREATE TABLE `schoolwithusers` (
  `id` int(11) NOT NULL,
  `school_id` int(11) DEFAULT NULL,
  `studentprofile_id` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

--
-- Dumping data for table `schoolwithusers`
--

INSERT INTO `schoolwithusers` (`id`, `school_id`, `studentprofile_id`) VALUES
(1, 1, 3),
(2, 3, 4);

-- --------------------------------------------------------

--
-- Table structure for table `studentprofile`
--

CREATE TABLE `studentprofile` (
  `id` int(11) NOT NULL,
  `user_id_fk` int(11) DEFAULT NULL,
  `rollno` int(11) DEFAULT NULL,
  `dob` date DEFAULT NULL,
  `attendence` int(11) DEFAULT NULL,
  `class` int(11) DEFAULT NULL,
  `section` enum('A','B') DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

--
-- Dumping data for table `studentprofile`
--

INSERT INTO `studentprofile` (`id`, `user_id_fk`, `rollno`, `dob`, `attendence`, `class`, `section`) VALUES
(1, 3, 22, '2022-01-21', 60, 1, 'A'),
(2, 4, 21, '2012-01-04', 45, 1, 'A'),
(3, 4, 1, '2012-01-04', 100, 3, 'B'),
(4, 5, 30, '2007-04-26', 45, 3, 'B'),
(5, 6, 2, '2022-01-19', 50, 6, 'B');

-- --------------------------------------------------------

--
-- Table structure for table `users`
--

CREATE TABLE `users` (
  `id` int(11) NOT NULL,
  `fname` varchar(45) DEFAULT NULL,
  `lname` varchar(45) DEFAULT NULL,
  `email` varchar(45) DEFAULT NULL,
  `password` varchar(45) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

--
-- Dumping data for table `users`
--

INSERT INTO `users` (`id`, `fname`, `lname`, `email`, `password`) VALUES
(1, 'Shashank', 'Naithani', 'shashank8036@gmail.com', 'lol123'),
(2, 'Kuldeep', 'Negi', 'negikuldeep@gmail.com', 'lop123'),
(3, 'Arpit', 'Thakut', 'Aptha@gmail.com', 'arp123'),
(4, 'Ankit', 'Barthwal', 'ankitbarth@gmail.com', 'ankit123'),
(5, 'Mukesh', 'Thakur', 'sasdb@gmail.com', 'sha123'),
(6, 'Arjun', 'Negi', 'sasdb@gmail.com', 'sha123');

--
-- Indexes for dumped tables
--

--
-- Indexes for table `exams`
--
ALTER TABLE `exams`
  ADD PRIMARY KEY (`id`),
  ADD KEY `examtye_id` (`examtye_id`) USING BTREE,
  ADD KEY `schooluser_id` (`schooluser_id`);

--
-- Indexes for table `examtype`
--
ALTER TABLE `examtype`
  ADD PRIMARY KEY (`id`);

--
-- Indexes for table `marks`
--
ALTER TABLE `marks`
  ADD PRIMARY KEY (`id`),
  ADD KEY `exam_id` (`exam_id`);

--
-- Indexes for table `roles`
--
ALTER TABLE `roles`
  ADD PRIMARY KEY (`id`);

--
-- Indexes for table `roles_assigned`
--
ALTER TABLE `roles_assigned`
  ADD PRIMARY KEY (`id`),
  ADD KEY `role_id` (`role_id`) USING BTREE,
  ADD KEY `user_id` (`user_id`) USING BTREE;

--
-- Indexes for table `schools`
--
ALTER TABLE `schools`
  ADD PRIMARY KEY (`id`);

--
-- Indexes for table `schoolwithusers`
--
ALTER TABLE `schoolwithusers`
  ADD PRIMARY KEY (`id`),
  ADD KEY `school_id` (`school_id`) USING BTREE,
  ADD KEY `studentprofile_id` (`studentprofile_id`);

--
-- Indexes for table `studentprofile`
--
ALTER TABLE `studentprofile`
  ADD PRIMARY KEY (`id`),
  ADD KEY `user_id_idx` (`user_id_fk`);

--
-- Indexes for table `users`
--
ALTER TABLE `users`
  ADD PRIMARY KEY (`id`);

--
-- AUTO_INCREMENT for dumped tables
--

--
-- AUTO_INCREMENT for table `exams`
--
ALTER TABLE `exams`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT;

--
-- AUTO_INCREMENT for table `examtype`
--
ALTER TABLE `examtype`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=4;

--
-- AUTO_INCREMENT for table `marks`
--
ALTER TABLE `marks`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT;

--
-- AUTO_INCREMENT for table `roles`
--
ALTER TABLE `roles`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=4;

--
-- AUTO_INCREMENT for table `roles_assigned`
--
ALTER TABLE `roles_assigned`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=13;

--
-- AUTO_INCREMENT for table `schools`
--
ALTER TABLE `schools`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=6;

--
-- AUTO_INCREMENT for table `schoolwithusers`
--
ALTER TABLE `schoolwithusers`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=3;

--
-- AUTO_INCREMENT for table `studentprofile`
--
ALTER TABLE `studentprofile`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=6;

--
-- AUTO_INCREMENT for table `users`
--
ALTER TABLE `users`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=7;

--
-- Constraints for dumped tables
--

--
-- Constraints for table `exams`
--
ALTER TABLE `exams`
  ADD CONSTRAINT `examtye_id` FOREIGN KEY (`examtye_id`) REFERENCES `examtype` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION,
  ADD CONSTRAINT `schooluser_id` FOREIGN KEY (`schooluser_id`) REFERENCES `schoolwithusers` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION;

--
-- Constraints for table `marks`
--
ALTER TABLE `marks`
  ADD CONSTRAINT `exam_id` FOREIGN KEY (`exam_id`) REFERENCES `exams` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION;

--
-- Constraints for table `roles_assigned`
--
ALTER TABLE `roles_assigned`
  ADD CONSTRAINT `role_id` FOREIGN KEY (`role_id`) REFERENCES `roles` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION,
  ADD CONSTRAINT `user_id` FOREIGN KEY (`user_id`) REFERENCES `users` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION;

--
-- Constraints for table `schoolwithusers`
--
ALTER TABLE `schoolwithusers`
  ADD CONSTRAINT `school_id` FOREIGN KEY (`school_id`) REFERENCES `schools` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION,
  ADD CONSTRAINT `studentprofile_id` FOREIGN KEY (`studentprofile_id`) REFERENCES `studentprofile` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION;

--
-- Constraints for table `studentprofile`
--
ALTER TABLE `studentprofile`
  ADD CONSTRAINT `user_id_fk` FOREIGN KEY (`user_id_fk`) REFERENCES `users` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION;
COMMIT;

Answer 1

您必须在主 key/foreign 键上加入每个 table。一些示例数据不太正确，因为您在 roles_assigned table 中有重复的 student_id 和 roles_id 值组合。请务必列出您需要的列名，而不是 *.

select * 
from users 
INNER JOIN roles_assigned ON users.id = roles_assigned.user_id 
INNER JOIN roles ON roles.id = roles_assigned.role_id
INNER JOIN studentprofile on studentprofile.id = users.id
INNER JOIN schoolwithusers on schoolwithusers.studentprofile_id = 
    studentprofile.id
INNER JOIN schools ON schools.id = schoolwithusers.school_id
WHERE roles.type = 'Student';

如何从 mysql 中的所有六个表中收集数据

how to gather data from all the six tabels in mysql

mysql

database

join