Immediate Food Delivery II
Task: Find the percentage of immediate orders in the first orders of all customers, rounded to 2 decimal places.
Table: Delivery
+-----------------------------+------+
| Column Name | Type |
+-----------------------------+------+
| delivery_id | INT |
| customer_id | INT |
| order_date | date |
| customer_pref_delivery_date | date |
+-----------------------------+------+
Input: Delivery table:
+-------------+-------------+------------+-----------------------------+
| delivery_id | customer_id | order_date | customer_pref_delivery_date |
+-------------+-------------+------------+-----------------------------+
| 1 | 1 | 2019-08-01 | 2019-08-02 |
| 2 | 2 | 2019-08-02 | 2019-08-02 |
| 3 | 1 | 2019-08-11 | 2019-08-12 |
| 4 | 3 | 2019-08-24 | 2019-08-24 |
| 5 | 3 | 2019-08-21 | 2019-08-22 |
| 6 | 2 | 2019-08-11 | 2019-08-13 |
| 7 | 4 | 2019-08-09 | 2019-08-09 |
+-------------+-------------+------------+-----------------------------+
Output:
+----------------------+
| immediate_percentage |
+----------------------+
| 50 |
+----------------------+