Question

I’m developing a site that is heavily dynamic and uses a MySQL database constantly. My question is – should I worry about the load on the database?
For example, a part of the site has a live chat which uses AJAX to contact the database every second for each user. Depending on how many users are connected, that’s a lot of queries!

Is this something a MySQL database can handle, or am I pushing it? Thanks.

Answer 1

You are actually pushing it. Depending on your server and online users count MySQL can handle at some point.

MySQL and other database management systems are data storage systems, and you are not actually storing the data! You are just sending data between clients through MySQL and that is not efficient.

But to speed things up, you can use MySQL Memory Tables for instant messages and keep offline messages in another MyISAM or InnoDB table (which will be storing the data)

But the best way to have a chat infrastructure is having a backend application which keeps all the messages in the memory, and after some limit sending not received messages to the MySQL as offline messages. This is very much like MySQL Memory Tables but you will have more control over the data. The problem with this is you need to implement logical and efficient data structures with good memory management, which is a very hard task if you are not doing a commercial product and unnecessary if you are not thinking about selling that chat system so I recommend use MySQL Memory Tables as I described.

Update
Mysql Memory Tables are volatile (will be reset on service/server restart), so don’t use it for storing, use only for keeping data in a short time for instant messages.