Three Levels Architecture Of Database Systems
Three Tier or Three level Architecture defines that how user access the at different level or we can say how data comes to the user in different level in DBMS.
In this DBMS we follow the three Tier Architecture:In this we go through three tiers i.e at three levels
Application Tier/ Business layer
An user operates/work on this tier with knowing the existence of a database beyond this layer. In this layer user sends a request to see or to do some task by using an application or software.
this tier is most important tier. this is kind of middle man which take request from presentation tier. and check this request if request is OK then it forward to database tier. Then this tier takes the output from database tier and forward to presentation tier.
Database (Data ) Tier:
In this tier we have a database system which process the request of application tier take a response and forward response / output to the application tier.