Which function returns the number of times a column appears?

Which function returns the number of times a column appears?

• A. count
• B. count distinct
• C. avg
• D. sum

Answer: (A)

Counting occurrences is what this function does. In data queries, an aggregate that returns a number representing how many records exist is the count function. It tallies each row (or each non-null value in a specific column) and gives you that total. The other options don’t provide a simple count: average calculates a mean, sum adds values, and count distinct tells you how many unique values appear—not the total number of occurrences. So, for determining how many times a column appears, the count function is the appropriate choice.

Counting occurrences is what this function does. In data queries, an aggregate that returns a number representing how many records exist is the count function. It tallies each row (or each non-null value in a specific column) and gives you that total. The other options don’t provide a simple count: average calculates a mean, sum adds values, and count distinct tells you how many unique values appear—not the total number of occurrences. So, for determining how many times a column appears, the count function is the appropriate choice.