Joins – ORACLE PL/SQL Chapter Wise Interview Questions

Joins – ORACLE PL/SQL Chapter Wise Interview Questions

Question 1:
What are various types of joins?
Answer:
Types of joins are:

1. Equijoins
2. Non-equijoins
3. Self join
4. Outer join

Question 2:
What is a Join and explain different types of joins.
Answer:
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.

Question 3:
What is a Self Join?
Answer:
Self Join is just like any other join, except that two instances of the same table will be joined in the query.