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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Previous SQL Exercise: Find the minimum purchase amount of all the orders.
Next SQL Exercise: Highest purchase amount ordered by the each customer.
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SQL: Tips of the Day
What is the best way to paginate results in SQL Server?
SELECT * FROM ( SELECT ROW_NUMBER() OVER ( ORDER BY OrderDate ) AS RowNum, * FROM Orders WHERE OrderDate >= '1980-01-01' ) AS RowConstrainedResult WHERE RowNum >= 1 AND RowNum < 20 ORDER BY RowNum
Database: SQL Server
Ref: https://bit.ly/3MGrNlk
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