I'm developing a chat project (server/client), so I will need an RDBMS for saving and loading user profiles, users logging-in etc., just like Skype does.
So my question is: which RDBMS will fit my needs?
There will be a lot of heavy queries like when users will log-in, all their profile information + their avatar picture will be queried from the DB and sent to the client app.
So imagine 1000 users are logging the same time, if successfully logged in then all these users will have their profile information + their avatar pic + their contacts list.