Note: Displaying Data from Multiple Tables in Oracle SQL (Use this join).

What is equi-join?

Equijoinisa join based on equality(=) or matching column values.

What is difference between inner join and equi join?

*’equi-join’ means joining tables using the equality operator(=) or equivalent.

*’inner join’ is determines how to join two sets when there is no matching value.

What is non equi-join?

Non-equi joins are joins whose join conditions use conditional operators (where, between) other than equals.

What is outer join?

In an outer join, unmatched rows in one or both tables can be returned.

Outer Join Example:

Select employees.employees_id, employees.employees_name,department.department_id, department.department_name,department.location_id form employees,department where employees_id(+)=department_id.

Outter Join use (+) on the query.

What is self join?

SELF JOIN a table is joined to own table.

Use || Concatanation operator to use between join query .

What is Cartesian-Products?

When not use join in query it’s call Cartesian-Products.

Cartesian-Products Example:

Select employees.employees_id, employees.employees_name,department.department_id, department.department_name,department.location_id form employees,department;