SQL Exercises: Find the largest number of orders booked by the customer
SQL Formatting Output: Exercise-9 with Solution
From the following table, write a SQL query that counts the unique orders and the highest purchase amount for each customer. Sort the result-set in descending order on 2nd field. Return customer ID, number of distinct orders and highest purchase amount by each customer.
Sample table: orders
SELECT customer_id, COUNT(DISTINCT ord_no), MAX(purch_amt) FROM orders GROUP BY customer_id ORDER BY 2 DESC;
Output of the Query:
customer_id count max 3002 3 5760.00 3009 2 2480.40 3005 2 948.50 3004 1 1983.43 3001 1 270.65 3007 1 2400.60 3008 1 250.45 3003 1 75.29
Relational Algebra Expression:
Relational Algebra Tree:
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Previous: From the following table, write a SQL query to find all the customers. Sort the result-set in descending order on 3rd field. Return customer name, city and grade.
Next: From the following table, write a SQL query to calculate summation of purchase amount, total commission (15% for all salesmen) by each order date. Sort the result-set on order date. Return order date, summation of purchase amount and commission.
What is the difficulty level of this exercise?
SQL: Tips of the Day
How to restore a dump file from mysqldump?
It should be as simple as running this:
mysql -u <user> -p < db_backup.dump
If the dump is of a single database you may have to add a line at the top of the file:
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