SQL Exercises: Highest grade for each of the cities of the customers

SQL Aggregate Functions: Exercise-8 with Solution

From the following table, write a SQL query to find the highest grade of the customers in each city. Return city, maximum grade.

Sample table: customer

Sample Solution:

SELECT city,MAX(grade) 
FROM customer 
GROUP BY city;

Output of the Query:

city		max
London		300
Paris		300
New York	200
California	200
Berlin		100
Moscow		200

Explanation Code

The said SQL statement retrieves the maximum "grade" value for each "city" in the 'customer' table. A "GROUP BY" clause is used in the query to group the 'customer' table according to a city, and a "MAX" function is used to determine the maximum grade for each group based on the "GROUP BY" clause.

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