Learn how to get Free YouTube subscribers, views and likes
Get Free YouTube Subscribers, Views and Likes

Are SQL joins bad for performance?

Follow
Database Star

 Get my free SQL Cheat Sheets: https://www.databasestar.com/getsql...
 Learn how to improve the performance of your SQL: https://databasestar.mykajabi.com/get...

Have you heard that SQL joins are bad and can slow down your queries? I've heard this too.

In this video, I'll demonstrate a query that joins three tables together along with the execution plan.
I'll also demonstrate the same query except all of the data is from one table, and the execution plan.

We'll then add some indexes and see what the execution plan looks like.

⏱ TIMESTAMPS:
00:00 Our test
01:18 Query 1
03:27 Query 2
04:28 Indexes
06:00 Check both queries

LINKS:
The sample database (olympics) is available on GitHub here: https://github.com/bbrumm/databasesta...
The script for the queries used in this video: https://github.com/bbrumm/databasesta...

posted by wynad2g