DATABASE FUNDAMENTALS
WHAT IS DATABASE MANAGEMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Representing database as seen by the DBMS mapping conceptual model to the DBMS
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Specific representation of an internal model
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Changing internal model without affecting the conceptual model
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None of the above
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Detailed explanation-1: -The internal schema defines the physical storage structure of the database. The internal schema is a very low-level representation of the entire database. It contains multiple occurrences of multiple types of internal record. In the ANSI term, it is also called “stored record’.
Detailed explanation-2: -That is, DBMSs utilize an internal schema, which represents the structure of the data as viewed by the DBMS, and an external schema, which represents various structures of the data as viewed by the end user.
Detailed explanation-3: -Internal models The three best-known models of this kind are the relational data model, the network data model and the hierarchical data model. These internal models: Consider a database as a collection of fixed-size records. Are closer to the physical level or file structure.
Detailed explanation-4: -The internal schema uses a physical data model and Page 2 describes the complete details of data storage and access paths for the database. 2. The conceptual level has a conceptual schema, which describes the structure of the whole database for a community of users.
Detailed explanation-5: -The internal model represents a database in the perspective view of a database. This model depicts a database as a collection of fixed-size records meaning that the database holds a fixed size. It can be pretty close to the physical layer/ File structure. It is the exact representation of the database.