Basics SQL

create database giraffe;
USE giraffe;

CREATE TABLE student (student_id INT PRIMARY KEY , 
name VARCHAR(30), 
/* ENTRY DEFAULT VALUE BY GIVING A DEFAULT CONSTRAINT */
major VARCHAR(30) DEFAULT 'Undecided');
DESCRIBE student;

/* DROP ENTIRE TABLE */
DROP TABLE student;

/* DROP A COLUMN IN A TABLE */
ALTER TABLE student DROP COLUMN gpa;  
ALTER TABLE student ADD gpa DECIMAL(3,2);


/* INSERTING DATA IN A TABLE */
INSERT INTO student VALUES(1,'Zafer','CSE',9.75);
INSERT INTO student VALUES(2,'Katrina','CSE',9.85);

/* SKIP A PARTICULAR COLUMN VALUE IN A TABLE */
INSERT INTO student(student_id,name,gpa) VALUES(3,'Regina',9.85);

/* LOOK EVERYTHING INSIDE THE TABLE */
SELECT * FROM student;

/* UPDATE VALUES IN A PARTICULAR ROW */
SET SQL_SAFE_UPDATES = 0;
UPDATE student  
SET major ='Mathematics'
WHERE major = 'Maths' ;
SET SQL_SAFE_UPDATES = 1;


/* DROP A ROW IN A TABLE */
DELETE FROM student WHERE student_id =2;