3-Level architecture in DBMS (Traditional model)

3 Level architecture: 

It was two organisation ANSINC & SPARCE in 1972 proposed three level architecture: 

• External or View level 
• Conceptual or Logical Level 
• Internal or Physical Level    

External Level: It describe only the part of database. The external level is one which is closest to the user. It is the way of How data is view by the individual users.

Conceptual Level:  It describe What data are stored in database & what relationship exists among those data. The conceptual level is called schema. 

Internal Level: This level represent how data are actually stored in database. It defines how to position data on the H/W & how to locate that data.