-- create a table
CREATE TABLE students (
  student_id INTEGER PRIMARY KEY,
  FirstName VARCHAR(50) NOT NULL,
  LastName VARCHAR(50) NOT NULL,
  Grade INT
);

CREATE TABLE Results(
    student_id INT PRIMARY KEY,
    Subject VARCHAR(50),
    Marks INT
);
-- insert some values
INSERT INTO students (student_id,FirstName,LastName,Grade) VALUES
(1,'John','Doe',7),
(2,'Jane','Smith',5),
(3,'Michael','Johnson',4),
(4,'Emily','Brown',8),
(5,'Alice','Jackson',6),
(6,'Jake','Joe',7);

INSERT INTO Result(student_id,Subject,Marks) VALUES
(1,'Coding',22),
(2,'Coding',23),  
(3,'Science',20),
(4,'English',25),
(5,'French',24);

-- Basic SQL Queries for School Data 
-- Select all Grade 7 students:

SELECT *FROM students 
WHERE Grade=7;

-- --Count the number of Grade 7 students

-- SELECT COUNT(*) FROM students
-- WHERE Grade=7

--Find the student with a specific StudentID:

SELECT *FROM students
WHERE student_id = 4;

UPDATE students SET Grade=7
WHERE student_id=3;

SELECT *FROM students;

--Check the marks for student where student_id=5;
SELECT marks *FROM Results
WHERE student_id=5;