Question

I need at select rows from table, make numbering rows so: first 3 rows numbering as:

1  
2  
3

and after ( from the fourth row ), start numbering again and this second numbering continue to the end of all records, that is result must be like this:

1  
2  
3  
1  
2  
3  
4  
5  
....  
....  
777

I write this query, but this returns usual numbering, from 1 to last record.

Please, someone tell me, where have I logical wrong in my query? In my opinion, this will returns numbring, as I write above

mysql-> SET @n = 0
mysql-> SET @start_again = 'true'


SELECT 

        CASE 
            WHEN  @n = 3 AND @start_again = 'true' THEN  @n := 1
            ELSE @n := @n + 1
        END,

        CASE 
            WHEN  @n = 3 AND @start_again = 'true' THEN  @start_again := 'false'
        END

FROM mytable

Answer 1

You’re overcomplicating your task.

SET @n = 0
SELECT if((@n := @n + 1) > 3, @n - 3, @n) AS n ...