This is a cheat sheet that I have put together for keeping track of the results of ordering different types of columns in ASC and DESC order and the rules around each. This order is fairly standard for most ANSI database servers. However I do not believe that there is anything in the ANSI spec that dictates this as a requirement.
Sort type |
DESC |
ASC (default) |
|---|---|---|
| NULL | NULL last | NULL first |
| Numerical | 10
9 8 ... 1 0 |
0
1 2 .. 10 11 |
| Alphabetical CI
(CI vs CS has an impact here as CI sees no difference between A and a but CS does! see below) |
Z
Y X ... A |
A
B C ... Z |
| Dates | 2019
2018 2017 ... 1907 |
1907
1908 1909 ... 2019 |
| ALPHAbetical CS | Lowercase first
Uppercase last |
Uppercase first
Lowercase last |