Which SQL function would you use to count rows that satisfy a condition?

Which SQL function would you use to count rows that satisfy a condition?

• A. SUM
• B. AVG
• C. MAX
• D. COUNT

Answer: (D)

Counting how many rows meet a condition is done with the COUNT function in SQL. You’d typically write a query like SELECT COUNT(*) FROM table WHERE condition, and COUNT tallies every row that satisfies that condition. COUNT(*) counts all matching rows, while COUNT(column) counts non-null values in a specific column, which is a slightly different way to measure data. The other options perform different tasks: SUM adds up numeric values across rows, AVG computes the average of numeric values, and MAX finds the largest value. They don’t count rows that meet a condition, which is why COUNT is the appropriate choice for this requirement.

Counting how many rows meet a condition is done with the COUNT function in SQL. You’d typically write a query like SELECT COUNT() FROM table WHERE condition, and COUNT tallies every row that satisfies that condition. COUNT() counts all matching rows, while COUNT(column) counts non-null values in a specific column, which is a slightly different way to measure data.

The other options perform different tasks: SUM adds up numeric values across rows, AVG computes the average of numeric values, and MAX finds the largest value. They don’t count rows that meet a condition, which is why COUNT is the appropriate choice for this requirement.