PostgreSQL Subqueries Tutorial for Beginners | Scalar & List Subquery with Practical Examples
In this video, we will learn Subqueries in PostgreSQL in a simple and practical way.
A subquery means writing a query inside another query. It is also called an inner query or nested query. Subqueries are very useful when you need to calculate something first and then use that result in another SQL query.
In this PostgreSQL tutorial, we will understand what is wrong with normal aggregate queries, why we need subqueries, and how scalar subqueries and list subqueries work with real examples.
We will also cover the syntax of subqueries, best practices, tips and tricks, and live practical query solving so that you can understand how to use subqueries in real projects.
In this video, you will learn:
What is a subquery in PostgreSQL?
Why do we need subqueries?
What is a scalar subquery?
What is a list subquery?
Difference between scalar subquery and list subquery
How to use subqueries with WHERE clause
How to use AVG(), MAX(), and IN with subqueries
PostgreSQL subquery syntax
Best practices for writing clean subqueries
Practical PostgreSQL subquery examples
This video is perfect for beginners who are learning PostgreSQL, SQL queries, database concepts, and backend development.
------------------------------------------------------------------------------------
🔗 Useful Playlists
📘 Next.js Full Stack Playlist:
https://youtube.com/playlist?list=PLwGdqUZWnOp0lwvSBaIzzgV9X0ZiZ-42O&si=aQ_TNBNNx5L7V_bn
⚛️ React.js Playlist:
https://youtube.com/playlist?list=PLwGdqUZWnOp1Rab71vx2zMF6qpwGDB2Z1&si=sDZRxsYNetYmojKd
💻 TypeScript Playlist:
https://youtube.com/playlist?list=PLwGdqUZWnOp0xfHQFmlL52b_6-QZ0mnk_&si=c4jfsd5ElDC1p0A5
------------------------------------------------------------------------------------
💸 Get All My YouTube Videos' Source Code for just ₹199! Grab Now - https://thapatechnical.shop/source-code
📺 Watch the complete Node.JS Playlist here :https://youtube.com/playlist?list=PLwGdqUZWnOp3KELplHtc-RnJ5xTUPqdgH&si=_ob8F88HYxCdspup
🔥 Access Source Code, PPT & Notes here for Free : https://www.thapatechnical.com/2024/11/introduction-to-nodejs.html
------------------------------------------------------------------------
🚀 Boost Your Skills with these Pre-Requisite Videos:
🔗 Best HTML Course - https://youtu.be/5ccq_nLHneE
🔗 Best CSS Course - https://youtu.be/MSICFljRcb4
🔗 JavaScript Basics Course Part 1 - https://youtu.be/13gLB6hDHR8
🔗 JavaScript Advanced Course Part 2 - https://youtu.be/YwsOCN8woA8
------------------------------------------------------------------------
💸 Build Your Own E-commerce Website for Free! - https://www.thapatechnical.com/2024/03/build-complete-ecommerce-website-using.html
------------------------------------------------------------------------
✌️ Join Us!
🚀 Become a Member: Unlock perks, free source code, and more Join Now : https://www.youtube.com/channel/UCwfaAHy4zQUb2APNOGXUCCA/join
📷 Connect on Instagram: https://www.instagram.com/thapatechnical
🗨️ Join Our Discord Server: Hang out with fellow programmers Discord Link: https://discord.gg/MdScmCsua6
------------------------------------------------------------------------
⌛TIMELINE⏳
0:00 Intro to Subqueries in PostgreSQL
0:20 What is wrong with this query?
1:10 What is a subquery?
2:10 Types of subqueries
3:30 Scalar subquery explained
5:20 List subquery explained
7:30 Syntax of subqueries
8:40 Best practices, tips and tricks
10:30 Query 1 - Practical session
11:53 Query 2 - Practical session