SQL Exercise: Using precedence with specified condition

SQL Boolean Operator Statement: Exercise-10 with Solution

Write a SQL query that displays order number, purchase amount, and the achieved and unachieved percentage (%) for those orders that exceed 50% of the target value of 6000.

Sample table: orders

ord_no      purch_amt   ord_date    customer_id  salesman_id
----------  ----------  ----------  -----------  -----------
70001       150.5       2012-10-05  3005         5002
70009       270.65      2012-09-10  3001         5005
70002       65.26       2012-10-05  3002         5001
70004       110.5       2012-08-17  3009         5003
70007       948.5       2012-09-10  3005         5002
70005       2400.6      2012-07-27  3007         5001
70008       5760        2012-09-10  3002         5001
70010       1983.43     2012-10-10  3004         5006
70003       2480.4      2012-10-10  3009         5003
70012       250.45      2012-06-27  3008         5002
70011       75.29       2012-08-17  3003         5007
70013       3045.6      2012-04-25  3002         5001

Sample Solution :

-- This query selects specific columns 'ord_no', 'purch_amt', and calculates two additional columns.
-- It calculates the percentage of the achieved and unachieved amounts based on a target of 6000.
SELECT ord_no, purch_amt,
       -- Calculates the percentage of the achieved amount.
       (100 * purch_amt) / 6000 AS "Achieved %",
       -- Calculates the percentage of the unachieved amount.
       (100 * (6000 - purch_amt) / 6000) AS "Unachieved %"
-- Specifies the table from which to retrieve the data (in this case, 'orders').
FROM orders
-- Filters the rows to only include those where the percentage of the achieved amount is greater than 50%.
WHERE (100 * purch_amt) / 6000 > 50;

Output of the Query:

ord_no	purch_amt	Achieved %			Unachieved %
70008	5760.00		96.0000000000000000	4.0000000000000000
70013	3045.60		50.7600000000000000	49.2400000000000000

Code Explanation:

The SQL query that is selecting specific columns "ord_no, purch_amt, (100*purch_amt)/6000 AS "Achieved %", (100(6000-purch_amt)/6000) AS "Unachieved %" from the 'orders' table where (100*purch_amt)/6000 is greater than 50.
Using mathematical expressions, the query calculates the percentage of achieved and unachieved amounts based on the value of the "purch_amt" column and a fixed value of 6000 as the value of the "purch_amt" column.
This query will return all rows in the table 'orders' that have a achieved percentage of greater than 50 as well as the selected columns in each row.

Explanation :

Visual presentation:

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