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college

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CREATE TABLE Department (     dept_id INT PRIMARY KEY,     name VARCHAR(50) ); CREATE TABLE Students (     reg_no INT PRIMARY KEY,     name VARCHAR(50),     address VARCHAR(100),     bcourse VARCHAR(50),     dept_id INT,     FOREIGN KEY (dept_id) REFERENCES Department(dept_id) ); CREATE TABLE Teachers (     teacher_id INT PRIMARY KEY,     name VARCHAR(50),     email VARCHAR(100),     address VARCHAR(100),     dept_id INT,     FOREIGN KEY (dept_id) REFERENCES Department(dept_id) ); CREATE TABLE Courses (     course_id INT PRIMARY KEY,     name VARCHAR(50),     credits INT,     dept_id INT,     teacher_id INT,     FOREIGN KEY (dept_id) REFERENCES Department(dept_id),     FOREIGN KEY (teacher_id) REFERENCES Teachers(teacher_id) ); CREATE TABLE Library (     library_id INT P...

company

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-- 1. Create DEPARTMENT (basic, no FK yet) CREATE TABLE DEPARTMENT (     Dname VARCHAR(50) NOT NULL,     Dnumber INT PRIMARY KEY,     Mgr_ssn CHAR(9),     Mgr_start_date DATE ); -- 2. Create EMPLOYEE CREATE TABLE EMPLOYEE (     Fname VARCHAR(20),     Minit CHAR(1),     Lname VARCHAR(20),     Ssn CHAR(9) PRIMARY KEY,     Bdate DATE,     Address VARCHAR(100),     Sex CHAR(1),     Salary DECIMAL(10,2),     Super_ssn CHAR(9),     Dno INT,     FOREIGN KEY (Super_ssn) REFERENCES EMPLOYEE(Ssn),     FOREIGN KEY (Dno) REFERENCES DEPARTMENT(Dnumber) ); -- 3. Alter DEPARTMENT (add manager FK → EMPLOYEE) ALTER TABLE DEPARTMENT ADD CONSTRAINT fk_mgr FOREIGN KEY (Mgr_ssn) REFERENCES EMPLOYEE(Ssn); -- 4. Create DEPT_LOCATIONS CREATE TABLE DEPT_LOCATIONS (     Dnumber INT,     Dlocation VARCHAR(50),     PRIMARY KEY ...