123
Linux 磁盘空间还有，但数据无法写入是什么原因？ inode SQL 练习表 在数据库中执行该sql语句，创建练习表 -- 创建部门表 CREATE TABLE departments ( department_id INT PRIMARY KEY, department_name VARCHAR(100) NOT NULL ); -- 插入部门数据 INSERT INTO departments VALUES (1, 'Engineering'), (2, 'Human Resources'), (3, 'Marketing'), (4, 'Finance'); -- 创建员工表 CREATE TABLE employees ( employee_id INT PRIMARY KEY, first_name VARCHAR(50), last_name VARCHAR(50), gender CHAR(1), hire_date DATE, department_id INT, FOREIGN KEY (department_id) REFERENCES departments(department_id) ); -- 插入员工数据 INSERT INTO employees VALUES (101, 'Alice', 'Smith', 'F', '2015-03-01', 1), (102, 'Bob', 'Johnson', 'M', '2017-07-15', 1), (103, 'Carol', 'Williams', 'F', '2019-01-10', 2), (104, 'David', 'Brown', 'M', '2018-11-23', 3), (105, 'Eve', 'Davis', 'F', '2020-06-17', 4); -- 创建薪资表 CREATE TABLE salaries ( salary_id INT PRIMARY KEY, employee_id INT, salary DECIMAL(10,2), from_date DATE, to_date DATE, FOREIGN KEY (employee_id) REFERENCES employees(employee_id) ); -- 插入薪资数据 INSERT INTO salaries VALUES (1, 101, 80000, '2020-01-01', '2021-12-31'), (2, 101, 85000, '2022-01-01', '9999-12-31'), (3, 102, 75000, '2019-01-01', '9999-12-31'), (4, 103, 60000, '2019-01-10', '9999-12-31'), (5, 104, 72000, '2018-11-23', '9999-12-31'), (6, 105, 68000, '2020-06-17', '9999-12-31'); -- 创建项目表 CREATE TABLE projects ( project_id INT PRIMARY KEY, project_name VARCHAR(100), start_date DATE, end_date DATE ); -- 插入项目数据 INSERT INTO projects VALUES (1, 'Project Apollo', '2021-01-01', '2021-12-31'), (2, 'Project Zephyr', '2022-03-01', NULL), (3, 'Project Orion', '2020-06-01', '2021-06-30'); -- 创建员工-项目关系表（多对多） CREATE TABLE employee_projects ( employee_id INT, project_id INT, role VARCHAR(50), PRIMARY KEY (employee_id, project_id), FOREIGN KEY (employee_id) REFERENCES employees(employee_id), FOREIGN KEY (project_id) REFERENCES projects(project_id) ); -- 插入员工项目关系数据 INSERT INTO employee_projects VALUES (101, 1, 'Developer'), (101, 2, 'Lead Developer'), (102, 1, 'Tester'), (103, 2, 'HR Manager'), (104, 3, 'Marketing Lead'), (105, 2, 'Accountant'); ...