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

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:

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.