Question

Let’s say I have a table like this:

name          |order_id
=======================
first_record  | 0
second_record | 0
third_record  | 0
       [...]

I want to update just order_id with an incremented value (not sure how to put this correctly in english – feel free to edit with a better description). See expected output below:

name          |order_id
=======================
first_record  | 1
second_record | 2
third_record  | 3
       [...]  | n

I know how to do this either by using a script in some programming language or a sql procedure, both solution involve looping the whole table.

Answer 1

You can update table:

 SET @oo = 0;
 UPDATE table SET `order_id`=@oo:=@oo+1 ORDER By something;

Or just get order_id as returned row number while selecting:

 SET @oo = 0;
 SELECT name, @oo:=@oo+1 order_id FROM table ORDER By something;