We have a project which very resource consuming in databse part and we found that database hosting which is satisfied our needs is lot money consuming.
We want to built own server and connect our database to it. The question is how to make our server avaliable from internet.
You generally do not want to make your database server accessible from the general internet. Where do the applications run that need this database? Try to install the database server there too. If that cannot be done, create a VPN or ipsec tunnel between the application and the database and make sure the database is accessible only through that tunnel. How that is done depends on the database and the operating system, so you will need to give us a lot more details if you want us to (be able to) help you.