how to customize any other way to query

Question

Hi team,

I'm trying to optimize this query size and best method, please let me share if have any best ideas on this optimize.

select '0sce to 2sec' as Bucket_Name,count(*) from tbllog 
where DATE_PART('second', endtimestamp::timestamp - starttimestamp::timestamp) <=2 and Process= @Process and  starttimestamp >= @StartTime and starttimestamp < @EndTime Union select '2sec to 5sec' as Bucket_Name,count(*) 
from tbllog  where Process= @Process and starttimestamp >= @StartTime 
and starttimestamp < @EndTime and DATE_PART('second', endtimestamp::timestamp - starttimestamp::timestamp)<=5 and DATE_PART('second', endtimestamp::timestamp - starttimestamp::timestamp)> 2 Union select '5sec to 10sec' as Bucket_Name,count(*) 
from tbllog   
where Process= @Process and starttimestamp >= @StartTime and starttimestamp < @EndTime and DATE_PART('second', endtimestamp::timestamp - starttimestamp::timestamp)<=10 
and DATE_PART('second', endtimestamp::timestamp - starttimestamp::timestamp)> 5 Union select 'Greater than 10sec' as Bucket_Name, count(*) from tbllog  
where Process= @Process and starttimestamp >= @StartTime and starttimestamp < @EndTime and DATE_PART('second', endtimestamp::timestamp - starttimestamp::timestamp)>10 ) 
ORDER BY Bucket_Name

Thanks