In this DBMS tutorial, you will learn what is mapping in DBMS and its types with suitable diagrams.
What is Mapping in DBMS?
The process of transforming a request and result between three levels is called mapping. The user’s request is specified at an external level which must be transferred at a conceptual level. Finally, this request is transformed at an internal level for the final processing of data in the stored database.
Hence mapping in DBMS is used to interconnect the three levels of databases.
Block Diagram of Mapping
Types of Mapping in DBMS
There are two types of mapping in DBMS as shown below:
The process of transforming requests and results between external and conceptual levels is called external/conceptual mapping. As shown in the above mapping block, the diagram, external views are connected to conceptual views with the help of external/conceptual mapping.
The conceptual schema is connected to the internal schema with the help of conceptual/internal mapping. This enables DBMS to finalize the actual record in physical storage. The process of transforming requests and results between the conceptual and internal levels is called conceptual/external mapping.