Previously, you learnt about nested queries, which are used to retrieve data from multiple tables. However, as you must have noticed, a nested query refers to only one table at a time. What if you want to refer to multiple tables in a single query? In such a case, you can use joins. Joins are a handy tool for outputting data from multiple tables in a single table.
You will also understand the set theory and some types of set operations. After this session, you will be able to perform set operations on your data using some SQL keywords. For example, you will be able to get the output of two separate queries in a single query using the ‘union’ operator.
In this session
You will learn the basics of set theory. The basic set operations are as follows:
- Union
- Intersection
- Difference
You will also learn about various types of joins, such as follows:
- Inner join
- Left join
- Right join
People you will hear from in this session
Subject Matter Expert
Professor & Dean (Academics), IIIT-B
The International Institute of Information Technology, Bangalore, popularly known as IIIT Bangalore, is a premier national graduate school in India. Founded in 1999, it offers Integrated M.Tech., M.Tech., M.S. (Research) and PhD programs in the field of Information Technology.