In SQL, when is the wildcard operator (e.g., %, _, *, ?) in a WHERE clause particularly useful?

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Solve this multiple-choice question and choose the correct option.

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Introduction / Context:Wildcards allow pattern matching when filtering rows in SQL queries. They are key to flexible searches in WHERE clauses. Given Data / Assumptions: We are considering the WHERE clause of a SELECT query. The goal is to match text patterns when exact values are unknown. Concept / Approach:The LIKE operator with wildcards (% or _) in SQL-92, or * and ? in Access, allows flexible pattern matching. This is used when an exact match cannot be provided. Step-by-Step Solution: Identify context: SELECT + WHERE clause.Check goal: matching without full exact string known.Answer: useful when exact match not possible in SELECT. Verification / Alternative check:SQL query example: SELECT * FROM customer WHERE name LIKE 'Sm%'. Why Other Options Are Wrong:Exact match cases: Do not require wildcards. CREATE statements: Wildcards are not applicable to schema creation. Common Pitfalls:Trying to use wildcards outside of WHERE clause context. Final Answer:An exact match is not possible in a SELECT statement.

In SQL, when is the wildcard operator (e.g., %, _, *, ?) in a WHERE clause particularly useful?

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