Lecture5.md

SELECT FROM

GROUP BY ; ...

Sample Command-

SELECT Name FROM students2 GROUP BY Name;

SELECT Name, COUNT(*) FROM students2 GROUP BY Name;

SELECT Marital_Status, AVG(Score) FROM students2 GROUP BY Marital_Status;

SELECT Name, AVG(Score) FROM students2 GROUP BY Name ORDER BY Name;

SELECT Name, Score FROM students2 GROUP BY Name; // Not Allowed (Error expected)

SELECT , {Aggreagate functions} FROM

GROUP By HAVING {Conditions}; ...

Sample Command -

SELECT Name, AVG(Score) as Average FROM students2 GROUP BY Name Having Average>70;

SELECT Marital_Status, COUNT(*) AS Number FROM students2 GROUP BY Marital_Status HAVING Number>2;

SELECT Marital_Status, COUNT(*) AS Number FROM students2 GROUP BY Marital_Status HAVING Number>3;

SELECT Marital_Status, COUNT(*) AS Number FROM students2 GROUP BY Marital_Status HAVING Number>5;

SELECT Marital_Status, AVG(Score) AS Average FROM students2 GROUP BY Marital_Status HAVING Marital_Status = "Married";

SELECT Marital_Status, AVG(Score) AS Average FROM students2 WHERE Marital_Status = "Married" GROUP BY Marital_Status; // Same query as above using where instead of Having clause. Same output