In SQL, which of the following are considered comparison operators for evaluating conditions in a WHERE clause?

Introduction / Context:
SQL queries frequently use conditions in WHERE clauses to filter rows. These conditions rely on comparison operators that compare column values to constants or expressions. Understanding which operators function as comparison operators helps in reading and writing expressive queries. This question asks you to identify which among LIKE, BETWEEN, and the equal operator are comparison operators.

Given Data / Assumptions:

• We are working with WHERE clauses in SQL.
• The operators in question are LIKE, BETWEEN, and the equal sign.
• The options include each operator individually, all of them together, and none of them.
• We assume familiarity with basic SQL query syntax.

Concept / Approach:
A comparison operator is any operator that compares a value with another value or expression and returns a logical result, typically true or false for each row. The equal sign compares two values for equality. LIKE compares a text value against a pattern and returns true when the value matches the pattern. BETWEEN checks whether a value lies within a specified range of values. All three operators are used to compare values and therefore are considered comparison operators in SQL.

Step-by-Step Solution:
Step 1: Recall that the equal sign is the simplest comparison operator, testing for equality. Step 2: Recognize that LIKE compares strings against patterns with wildcard characters. Step 3: Recognize that BETWEEN compares a value with two boundary values, checking whether it falls within the range. Step 4: Understand that all three operators return true or false for each row, which fits the definition of comparison operators. Step 5: Based on this, conclude that all three are comparison operators, making option d the correct choice.

Verification / Alternative check:
Consider the query SELECT * FROM products WHERE price BETWEEN 100 AND 200. Here BETWEEN is clearly comparing price to a lower and an upper bound. In SELECT * FROM customers WHERE name LIKE 'A%', the LIKE operator compares the name to a pattern. In SELECT * FROM orders WHERE status = 'SHIPPED', the equal operator compares status to a constant. Each operator acts as a comparison in its own way, returning results based on whether the condition is satisfied.

Why Other Options Are Wrong:
LIKE alone, BETWEEN alone, or the equal operator alone cannot be the answer in this multiple choice format because the question asks which of the following are comparison operators, and all three truly are. None of the above is clearly wrong because the options do list valid comparison operators.

Common Pitfalls:
Students sometimes associate comparison operators only with numeric comparisons such as greater than or less than and forget that pattern matching and range testing are also comparisons. It is also important to know that these operators can interact with indexes differently, which can affect performance, but conceptually they all belong in the comparison family.

Final Answer:
All the listed operators are comparison operators, so the correct choice is All of the above.