What is a join and explain different types of joins

- Joins are used in queries to explain how different tables are related.

- Joins also let you select data from a table depending upon data from another table.


Types of joins: INNER JOINs, OUTER JOINs, CROSS JOINs.

OUTER JOINs are further classified as LEFT OUTER JOINS, RIGHT OUTER JOINS and FULL OUTER JOINS.


What is a join and explain different types of joins.


- Joins are utilized to get the results from two or more tables. There are two types of joins available.

1. Outer Join: Outer join has two categories – left outer join and right outer join. In this join functionality, two or more tables are joined by including blank rows in the specified side, once the criterion satisfies.


- The combination of left outer join and right outer join is simple outer join.

2. Inner Join: In this join functionality, two or more tables are joined by leaving the blank rows for checking.


- Other than these two joins, there are-

Natural Join: This join is the Cartesian product.

Equi Join: A condition includes an operator

NonEqui Join: They are conditional joins which does not use their conditions.


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