How to use ID JOIN instead of DATEDIFF() - sql

Question

Write a SQL query to find all dates' id with a higher temperature compared to its previous dates (yesterday).
Try out if you want: https://leetcode.com/problems/rising-temperature/
Input:
Weather table:
+----+------------+-------------+
| id | recordDate | temperature |
+----+------------+-------------+
| 1 | 2015-01-01 | 10 |
| 2 | 2015-01-02 | 25 |
| 3 | 2015-01-03 | 20 |
| 4 | 2015-01-04 | 30 |
+----+------------+-------------+
Output:
+----+
| id |
+----+
| 2 |
| 4 |
+----+
Here's my code:
SELECT w_2.id AS "Id"
FROM Weather w_1
JOIN Weather w_2
ON w_1.id + 1 = w_2.id
WHERE w_1.temperature < w_2.temperature
But my code won't be accepted even if it looks exactly like the expected output.
I know the answer is:
SELECT w2.id
FROM Weather w1, Weather w2
WHERE w2.temperature > w1.temperature
AND DATEDIFF(w2.recordDate, w1.recordDate) = 1
But I tried to not use DATEDIFF because this function is not available in PostgreSQL.

Answer 1

The queries are not compatible. You should join the table on recordDate, not on Id.
SELECT w_2.id AS "Id"
FROM Weather w_1
JOIN Weather w_2
ON w_1.recordDate + 1 = w_2.recordDate
WHERE w_1.temperature < w_2.temperature
Do not assume that Id is sequential and ordered in the same way as recordDate, although the sample data may suggest this.