In the context of DBMS, consider the two sets T and S given below.
T
S
I: Logical schema
L: Views
II: Physical schema
M: File organization and indexes
III: External schema N: Relations
Which one of the following is the correct match from T to S ?
In the context of DBMS, consider the two sets T and S given below.
T
S
I: Logical schema
L: Views
II: Physical schema
M: File organization and indexes
III: External schema N: Relations
Which one of the following is the correct match from T to S ?
Show Hint
- I - L, II - M, III - N
- I - M, II - L, III - N
- I - N, II - M, III - L
- I - N, II - L, III - M
The Correct Option is C
Solution and Explanation
Step 2: The physical schema describes how the data is actually stored on disk, including file organization and the indexes used for efficient access.
Step 3: The external schema describes the database as seen by individual users or applications, which corresponds to views built on top of the underlying relations.
Step 4: Matching accordingly: Logical schema (I) corresponds to Relations (N); Physical schema (II) corresponds to File organization and indexes (M); External schema (III) corresponds to Views (L).
Final Answer: Option (C): I - N, II - M, III - L
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