In SQL, the set of commands used for defining database schema objects (such as CREATE, ALTER, and DROP) make up which language category?
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ADDL
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BDML
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CHTML
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DXML
Answer
Correct Answer: DDL
Explanation
Introduction / Context:SQL statements can be classified based on their purpose. Data Definition Language (DDL) refers specifically to schema-level commands, which are critical for designing and maintaining database structures.
Given Data / Assumptions:
- DDL includes CREATE, ALTER, DROP, TRUNCATE.
- The question focuses on commands that define data structures.
Concept / Approach:DDL commands manage schema-level objects: tables, indexes, views. These operations change metadata and require commit/rollback handling depending on DBMS implementation.
Step-by-Step Solution:
Identify commands that create/alter/drop structures.Match them to DDL category.Confirm “DDL” is correct.Verification / Alternative check:Database manuals group CREATE TABLE and DROP TABLE under DDL, distinct from data manipulation (DML).
Why Other Options Are Wrong:DML: Affects data, not structure. HTML/XML: Document markup, unrelated to SQL schema definition.
Common Pitfalls:Confusing DDL with DML; remember DDL defines structure, DML manipulates data inside structures.
Final Answer:DDL