My question is same as [this one on SO](https://stackoverflow.com/questions/25945534/join-rows-from-two-different-queries), but difference is what should we do if random incremented `id` not continues.

**QUERY**
---------

```
create table sales_table (no int, date varchar(10), sales int);

insert into sales_table values (1, '1-Jan', 10000),
                               (3, '3-Jan', 12500),
                               (5, '4-Jan', 8000);

```

**EXPECTED RESULT**
-------------------

```
+-------+------------+--------------+-------------+
| no    |    date    |     sales    |      diff   |        
+-------+------------+--------------+-------------+
| 1     |    1-Jan   |     10,000   |       0     |         
| 3     |    3-Jan   |     12,500   |       2500  |            
| 5     |    4-Jan   |     8,000    |      -4500  | 
+-------+------------+--------------+-------------+

```