Equi join-table handling, Database Management System

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Equi Join: A join in which the joining condition is based on equality among values in the common columns. Common columns show (redundantly) in the result table. Let us Consider the following relations:

  • Customer (custid, custname, ...........) and
  • Order (custid, ordered,....................)

Example: What are the names of all customers who have placed orders?

The needed information is available in two tables, customer and order. The SQL solution needs joining the two tables by using equi join.

 SELECT CUSTOMER.CUTOID, ORDER.CUSTOID, CUSTONAME, ORDERID

FROM CUSTOMER, ORDER

WHERE CUSTOMER.CUSTOID=ORDER.CUSTOID;

The output might be:

Customer.custoid

order.custoid

custoname

orderid

--------------------------

------------------

-----------------------

----------

10

10

Pooja Enterprises

1001

12

12

Estern Enterprises

1002

3

3

Impressions

1003

 

 

 

 


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