Question

Let’s look at two tables, for example tables Post and User
In Post table, column user_id is foreign key.

Table Post

-id
-user_id
-post

Table User
-userID
-username

If we want to get poster’s username, we have to use join query and get it from User table.

Wouldn’t it be easier that we add extra column in Post table for storing posters’ usernames in order to simplify SQL queries. In this case, Post table would have user_id and username columns (username column is redundant) but that would eliminate join queries for catching posters’ usernames.

What is the best choice, to store usernames in Post table or not

Answer 1

Creating a view is an opition: and ust query that view. However, views in msql don’t offer as much benefit in terms of performance as they once did.

It might be that just running the join is fine. Depending on the amount of data you will eventually store you may need to consider other means to improve performance such as partitioning tables etc etc. – but that is for down-the-line