Equi-Joins

This is the most general type of joins. This join holds a condition containing an equality operator. The equi-join combines rows which have equivalent values for the columns specified in the Join. A simple instance for using Equi-Joins is shown follows.

Example

SELECT ename,dname FROM emp,dept WHERE emp.deptno=dept.deptno;#for display the employee name and department name of that employee#
The example will display all the e,ployees and their department names based on the outcome of the join condition.
In the example, the emp.deptno=dept.deptno is Join condition. The records are selected and displayed when the condition is become to TRUE.
The display will be:

ENAME         DNAME
KING          ACCOUNTING
BLAKE          SALES
CLARK       ACCOUNTING
JONES         RESEARCH
MARTIN        SALES
ALLEN         SALES
TURNER      SALES
JAMES        SALES
WARD        SALES
FORD       RESEARCH
SMITH      RESEARCH
SCOTT     RESEARCH
ADAMS     RESEARCH
MILLER     ACCOUNTING