In SQL pattern matching, which keyword is used together with wildcard characters such as percent (%) and underscore (_) to search for matching text?

Introduction / Context:
SQL provides pattern matching capabilities for searching text. Wildcard characters such as percent and underscore are commonly used to match any sequence of characters or a single character. To use these wildcards, you must pair them with a specific keyword in the WHERE clause. This question tests whether you know which keyword is appropriate.

Given Data / Assumptions:

• We are working with SQL queries that search text columns.
• Wildcard characters % and _ are mentioned.
• The options list LIKE, IN, NOT IN, combinations of IN and NOT IN, and BETWEEN.
• We assume basic familiarity with WHERE clauses.

Concept / Approach:
The LIKE operator in SQL is used for pattern matching in text strings. It is used together with wildcards, where percent matches any sequence of zero or more characters and underscore matches any single character. IN and NOT IN are used to test membership in a list of values, and BETWEEN checks whether a value lies within a range. None of these other operators use % or _ as wildcards in standard SQL.

Step-by-Step Solution:
Step 1: Recall that a typical pattern matching query looks like SELECT * FROM table WHERE name LIKE 'A%'. Step 2: Notice that the pattern 'A%' uses the percent wildcard to match any string starting with the letter A. Step 3: Understand that LIKE is the operator that interprets % and _ as wildcards. Step 4: Recognize that IN and NOT IN expect a fixed list of values and do not interpret % or _ as wildcards. Step 5: Acknowledge that BETWEEN is for numeric or date ranges and does not use wildcards either.

Verification / Alternative check:
If you run a query such as SELECT * FROM employees WHERE last_name LIKE '%son', you retrieve rows where last_name ends with son. Trying to use IN with a pattern like '%son' in the same way does not treat percent as a wildcard; it treats it as a literal character within a string. This confirms that LIKE is the correct operator for wildcard pattern matching.

Why Other Options Are Wrong:
IN only and NOT IN only are used for membership testing, not pattern matching. IN and NOT IN together is also incorrect, because neither supports wildcard characters as part of their semantics. BETWEEN is used for range checks and does not interpret percent or underscore in any special way.

Common Pitfalls:
Learners sometimes attempt to combine LIKE with IN, such as column IN ('A%', 'B%'). This does not work as expected because IN does not interpret patterns. Instead, you should combine multiple LIKE conditions with OR. Remember that wildcard pattern matching always uses LIKE (or sometimes ILIKE in case sensitive variants).

Final Answer:
The keyword used with wildcard characters in SQL pattern matching is LIKE only.