Fetch Only Common Records From Two Tables

I have two tables, which are student and student1. 

 

student

Select * from student

 

 

student1

Select * from student1

 

 

Query

(Select * from student) Intersect (Select * from student1)

Output

 

 

Now, you can see in both my tables that only common records are shown in our result set.

 

Explanation 

 

In this query, we have used Intersect; if you have knowledge about Algebra, then you must know it well. If you don't know, don't worry about it, as I am explaning it.

 

Intersection

 

Intersecion works on more than one result set. Intersecion is denoted by ∩. Intersection A ∩ B of two

sets A and B is the set, which contains all the elements of A, which also belong to B (or equivalently, all elements

of B that also belong to A), but no other elements. 

 

Let A={ Orange, pineapple, banana} and

Let B={ spoon,Orange, pineapple, mango}  

 

A ∩ B = {Orange, pineapple}

 

Same thing happens in our SQL query but this process is hidden..