Round to .5 or 1.0 in SQL

Question

I\'m looking to round values like

2.3913 -> 2.5

4.6667 -> 4.5

2.11 -> 2

How can I manage this in SQL?

Answer 1

SELECT ROUND(2.2 * 2, 0) / 2 

gets you to the nearest .5

Answer 2

round(round(column/5,1)*5,1) closest 0.5
round(round(column/5,2)*5,2) closest 0.05