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HackerRank: [SQL Aggregation] (5/17) JAPAN POPULATION | sum function in SQL

HackerRank: [SQL Aggregation - 5/17] Japan Population | SUM Function in SQL
I started studying SQL from a very famous site - HackerRank. Here I will try to provide multiple approaches & solutions to the same problem. It will help you learn and understand SQL in a better way.

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Click Here for the previous blog-post in the series.

SQL Problem Statement:

Query the sum of the populations for all Japanese cities in CITY. The COUNTRYCODE for Japan is JPN.

Input Format:

The CITY table is described as follows:

CITY Columns

Solution: Using SUM Function (MySQL Query):


  1. SUM is an aggregation function used to calculate the sum or total of the values of all the records in the specified column name passed to the function.

Sample Output:


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-Akshay P Daga

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