I have one table called as request
and there are three columns called as Id, want, teach
. I have to display want
and teach
co
You are not getting the point of multi order here.
firstly , by default, most of dbms sorting as ASC
.
Multiple ordering depending on the order of sorted columns, which is mean that -so to speak- :-
" hey sql ! select some result from my table , order them by col1 and group them by this order , then this sorted or grouped data set , sort them by col2. "
it's kind of multidimensional sorting so to speak.
take this as an example :
+------+---------+-------+ +------+---------+-------+
| id | want | teach | | id | want | teach |
+------+---------+-------+ +------+---------+-------+
| 1 | 1 | 2 | ORDER BY | 2 | 1 | 1 |
| 2 | 1 | 1 | want asc, | 1 | 1 | 2 |
| 3 | 2 | 1 | teach asc | 4 | 1 | 2 |
| 4 | 1 | 2 | | 3 | 2 | 1 |
+------+---------+-------+ +------+---------+-------+
and when you revert the order of sorted columns like this :
+------+---------+-------+ +------+---------+-------+
| id | want | teach | | id | want | teach |
+------+---------+-------+ +------+---------+-------+
| 1 | 1 | 2 | ORDER BY | 2 | 1 | 1 |
| 2 | 1 | 1 | teach asc, | 3 | 2 | 1 |
| 3 | 2 | 1 | want asc | 1 | 1 | 2 |
| 4 | 1 | 2 | | 4 | 1 | 2 |
+------+---------+-------+ +------+---------+-------+