View definitions and GROUP BY — evaluate the statement: “Standard SQL-92 views are constructed from SELECT statements that do not contain the GROUP BY clause.” Decide if this is correct or incorrect.

Introduction / Context: Views encapsulate SELECT queries. The question asks whether SQL-92 prohibits GROUP BY in view definitions. Understanding the difference between “can define” versus “can update through” is essential: aggregation affects updatability, not definability.

Given Data / Assumptions:

• We are discussing definitional capability (CREATE VIEW ... AS SELECT ...), not necessarily updatability.
• GROUP BY, HAVING, and aggregate functions may appear in SELECT statements.
• Vendors implement different updatability rules for aggregate views.

Concept / Approach: SQL-92 allows views to be defined using arbitrary SELECT statements, which may include GROUP BY. However, views that perform aggregation are typically not inherently updatable because grouping destroys the one-to-one correspondence with base rows. Hence, the statement that standard views are constructed only from SELECT without GROUP BY is incorrect; GROUP BY is allowed but usually produces a non-updatable view.

Step-by-Step Solution:

Verification / Alternative check: Try CREATE VIEW v AS SELECT dept_id, COUNT(*) AS c FROM emp GROUP BY dept_id; — this is valid in mainstream SQL systems, though INSERT/UPDATE via v will be restricted.

Why Other Options Are Wrong:

• Limiting GROUP BY to multi-table joins or claiming “undetermined” misunderstands the syntax rules.
• “Correct only for updatable views” mixes two separate topics; the stem asserts a blanket prohibition for standard views, which is false.

Common Pitfalls: Confusing syntactic allowance with updatability; assuming anything not updatable is disallowed in a view definition.

Final Answer: Incorrect