Question

Is it possible to delete in a while loop like iteration ?
ex:

id value
1 12
1 13 – should delete

1 14 – should delete
2 15.3
2 43 – should delete
2 22 – should delete

Now I need to delete every 2nd and 3rd ( i%2==0 || i%3==0 ) rows.

Answer 1

Try with this after taking a backup:

DROP TABLE IF EXISTS temptt;
CREATE TEMPORARY TABLE temptt (`id` INT, `value` INT);
INSERT INTO temptt 
    SELECT * FROM your_table GROUP BY id;
DELETE t1.* 
FROM your_table t1 LEFT JOIN temptt t2
    ON t1.id = t2.id AND t1.value = t2.value
WHERE t2.id IS NULL;

The idea is to insert data that should not be deleted in a temporary table and then delete all data in your_table that are not in that table.