Difficulty: Easy
Correct Answer: All of the above.
Explanation:
Introduction / Context:SQL emerged from the relational model to provide a declarative, vendor-neutral way to define schemas and manipulate data. Its scope covers both structure and data, enabling a complete lifecycle from creation to query to update using a single language.
Given Data / Assumptions:
Concept / Approach:
SQL's charter includes DDL (CREATE/ALTER/DROP) to define tables, keys, and constraints; DML (SELECT/INSERT/UPDATE/DELETE) to read and modify data; and related control statements for permissions and transactions. Therefore, its original purpose encompasses all items listed except operating-system concerns.
Step-by-Step Solution:
Map DDL responsibilities to structure definition and constraints.Map DML responsibilities to data retrieval and modification.Confirm that SQL was intended to unify these under one standard.Select the comprehensive choice: All of the above.Verification / Alternative check:
Historical papers on System R and standards documentation confirm SQL's dual role in structure and manipulation, later expanded by security and transaction controls.
Why Other Options Are Wrong:
Common Pitfalls:
Final Answer:
All of the above.
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