updating columns with a sequence number mysql

Question

I have a table with the columns: (this is only an example I have 50K records)

Name,   Number  Joe     Null Michael Null Moses   Null 

I to update the number with a sequence number from 1-3 so it will look like this:

Name,   Number  Joe     1 Michael 2 Moses   3 

How can I do it in SQL for Mysql in one SQL command

Answer 1

SET @rank:=0; update T set Number=@rank:=@rank+1; 

UPDATE

alternative way with one statement

UPDATE T JOIN (SELECT @rank := 0) r SET Number=@rank:=@rank+1;