Schema SQL (TO CREATE TABLE)

CREATE TABLE student(
student_id INT,
name VARCHAR(20) NOT NULL,
major VARCHAR(20) UNIQUE,
PRIMARY KEY(student_id)
);

Default values

CREATE TABLE student2(
student_id INT AUTO_INCREMENT,
name VARCHAR(20) ,
major VARCHAR(20) DEFAULT 'undecided',
PRIMARY KEY(student_id)
);

Constraints(optional) Not null=> value can't be null Unique=> other rows can't have same value for this column Default=> when value is not inserted, give default value Auto_increment=> Automatically create increasing numbers (1,2,3....) QUERY SQL (RUN QUERIES) Show table skeleton/layout;

DESCRIBE student;

Show actual table

SELECT * FROM student;

Add row

ALTER TABLE student ADD gpa DECIMAL(3,2);

Remove row

ALTER TABLE student DROP COLUMN gpa;

Remove table

DROP TABLE student;

Insert data in table

INSERT INTO student VALUES(1,'Jack','Biology');
INSERT INTO student(student_id, name) VALUES(1,'Claire');//major: null;

INSERT INTO student2(student_id,name); VALUES(1,'Jack'); //major: undecided


INSERT INTO student2; VALUES('Jack','Biology'); //student_id=>1
INSERT INTO student2; VALUES('BOB','Chemistry'); //student_id=>2