Using If else in SQL Select statement

Question

I have a select statement which will return 2 columns.

ID | IDParent

Then in my program I have to test if IDParent is < 1 then use

Answer 1

The query will be like follows

SELECT (CASE WHEN tuLieuSo is null or tuLieuSo=''
            THEN 'Chưa có đĩa' 
            ELSE 'Có đĩa' End) AS tuLieuSo,moTa
FROM [gPlan_datav3_SQHKTHN].[dbo].[gPlan_HoSo]