Joins – ORACLE PL/SQL Chapter Wise Interview Questions
What are various types of joins?
Types of joins are:
- Self join
- Outer join
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 Self Join?
Self Join is just like any other join, except that two instances of the same table will be joined in the query.