I have a system (develop by someone else) where all registered user can query data (similar to data.stackexchange.com). The system is getting big and more user query the system and during the high traffic time the database is slow and I am afraid of security now.

  1. What can I do to make the system more secure?
  2. What can I do to make the queries faster to execute?

I have a very basic knowledge of mysql and databases and I want to learn. Can you point where I need to look and what can I do? (I would like to build my self, so please no code)

mysql performance security
Edit
Report