1173 Immediate Food Delivery I

Description

Table: Delivery

• delivery_id is the primary key (column with unique values) of this table.
• The table holds information about food delivery to customers that make orders at some date and specify a preferred delivery date (on the same order date or after it).

If the customer’s preferred delivery date is the same as the order date, then the order is called immediate; otherwise, it is called scheduled.

Problem Statement

Write a solution to find the percentage of immediate orders in the table, rounded to 2 decimal places.

The result format is in the following example.

Example 1:

Input:

• Delivery table:

Output:

Explanation:

• The orders with delivery id 2 and 3 are immediate while the others are scheduled.

Solution

We need to find percentage of orders which are immediate orders. For this, you need to find total number of orders and the number of immediate orders. In order to find total number of orders, you can count the number of rows in the table. In order to find number of immediate orders, you can find the number of orders where order_date = customer_pref_delivery_date. Once you have these two numbers, you can divide the number of immediate orders by the total number of orders.

Finally, you need to round the result to 2 decimal places.

1SELECT ROUND(SUM(CASE WHEN order_date = customer_pref_delivery_date THEN 1 ELSE 0 END) /
2    COUNT(1) * 100, 2) AS immediate_percentage 
3    FROM Delivery;