Question 100 – Database-Management-System
May 14, 2024Question 157 – Database-Management-System
May 14, 2024Question 156 – Database-Management-System
Immunity of the external schemas (or application programs) to changes in the conceptual schema is referred to as:
Correct Answer: B
Question 246 Explanation:
→ Logical data independence:
The ability to change the Conceptual (Logical) schema without changing the External schema (User View) is called logical data independence. For example, the addition or removal of new entities, attributes, or relationships to the conceptual schema or having to rewrite existing application programs.
The ability to change the Conceptual (Logical) schema without changing the External schema (User View) is called logical data independence. For example, the addition or removal of new entities, attributes, or relationships to the conceptual schema or having to rewrite existing application programs.
→ Physical data independence:
The ability to change the physical schema without changing the logical schema is called physical data independence. For example, a change to the internal schema, such as using different file organization or storage structures, storage devices, or indexing strategy, should be possible without having to change the conceptual or external schemas.
Note: Immunity is when data at one layer is changed, it does not affect the data at another level.
Physical Data Independence
Logical Data Independence
Both (a) and (b)
None of the above
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