SQL Exercises: Find the highest purchase amount each customer ordered

SQL Aggregate Functions: Exercise-10 with Solution

From the following table, write a SQL query to find the highest purchase amount ordered by each customer on a particular date. Return, order date and highest purchase amount.

Sample table: orders

Sample Solution:

SELECT customer_id,ord_date,MAX(purch_amt) 
FROM orders 
GROUP BY customer_id,ord_date;

Output of the Query:

customer_id	ord_date	max
3002		2012-10-05	65.26
3003		2012-08-17	75.29
3005		2012-10-05	150.50
3007		2012-07-27	2400.60
3009		2012-08-17	110.50
3001		2012-09-10	270.65
3002		2012-09-10	5760.00
3005		2012-09-10	948.50
3009		2012-10-10	2480.40
3008		2012-06-27	250.45
3004		2012-10-10	1983.43
3002		2012-04-25	3045.60

Code Explanation:

The said SQL query retrieves the customer id, order date, and the maximum purchase amount for each combination of customer id and order date in the 'orders' table. The result will be grouped by customer id and order date.

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