（问题待解决）sql查询不显示前置‘0’的问题

SELECT *
,CONVERT(INT,progress)%60
,CONVERT(VARCHAR(10),(case when (CONVERT(INT,progress)%60)>9 then (CONVERT(DECIMAL,progress)%60)  else ‘012‘ end))
from CourseBooksNotes

DECLARE @a int=05
SELECT CONVERT(VARCHAR(10),@a/60)+‘分‘+CONVERT(VARCHAR(10),@a%60)+‘秒‘; 
SELECT CONVERT(VARCHAR(10),@a/3600)+‘时‘+CONVERT(VARCHAR(10),@a%3600/60)+‘分‘+CONVERT(VARCHAR(10),@a%3600%60)+‘秒‘