[Solved] What does the SQL function SUM(column_name) do in a PostgreSQL query? — Ans: Adds all the values in the specified column | PostgreSQL

PostgreSQL - Aggregate Functions and GROUP BY

What does the SQL function SUM(column_name) do in a PostgreSQL query?

ACalculates the average of the values in the column

BCounts the number of rows in the table

CFinds the smallest value in the column

DAdds all the values in the specified column

Step-by-Step Solution

Solution:

Step 1: Understand the purpose of SUM()
The SUM() function adds all numeric values in a column.
Step 2: Compare with other aggregate functions
COUNT counts rows, MIN finds smallest, AVG calculates average, so they differ from SUM.
Final Answer:
Adds all the values in the specified column -> Option D
Quick Check:
SUM() = Adds values [OK]

Quick Trick: SUM adds numbers, COUNT counts rows [OK]

Common Mistakes:

Master "Aggregate Functions and GROUP BY" in PostgreSQL

9 interactive learning modes - each teaches the same concept differently

What does the SQL function SUM(column_name) do in a PostgreSQL query?