用于将列的编号重新排序为奇数或全部偶数的SQL查询

Lets say I have a column that has 20 rows (it's more, but the concept will hold true for 20). Right now, the column is uniquely numbered 1-20. I need to figure out a query though that will change that number scheme from sequential, to sequential with just even or odd numbers.Lets say I have a column that has 20 rows (it's