How to calculate tenure of employee via SQL

SELECT login_name,job_title,

(cast(datediff(year,Column_name,getdate()) as varchar(20)) + 'year'+

cast(datediff(month, dateadd(year,datediff(year,Column_name,getdate()),Column_name)

,getdate()) as varchar(20)) + 'month'+

cast(datediff(day,getdate(),dateadd(month,datediff(month,

dateadd(year,datediff(year,Column_name,getdate()),Column_name),

getdate()),dateadd(year,datediff(year,Column_name,getdate()),Column_name)))

as varchar(20)) + 'day') as tenure

FROM table_name

all products