Question

I m sry if the title is not clear.

Here’s my proble.

I created a new table which will show total, average and maximum values.

I have to insert the results into that table.

That table will have only 4 rows. No Appointment, Appointment Early, Appointment Late and Appointment Punctual.

So.. I have sth like..

insert into newTable
select
'No Appointment' as 'Col1',
avg statement,
total statement,
max statement 
from orgTable
where (general conditions) and (unique condition to check NO APPOINTMENT);

I have to do that same thing for another 3 rows.. where only the unique condition is different to check early, punctual or late..

So..the statement is super long.

I wanna reduce the size.. How can I achieve that?

Answer 1

Complete proof-of-concept (now in Sql Server), and also we use CTE(the WITH clause) so we don’t need to repeat the specific conditions on GROUP BY clause; basically the logic of the program is to tag first the rows where specific condition they belong to, then from there we group them outside of WITH clause.

-- drop table attendance;
-- drop table yourtable;
create table attendance
(
arrived datetime
);



declare @d datetime;
set @d = GETDATE();




declare @t integer;
set @t = 0;

while @t < 50 begin

   insert into attendance select dateadd(hour, @t, @d);
   set @t = @t + 1;
end

select * from attendance;


create table yourtable
(
segment varchar(max),
total int,
the_max datetime
);


with tagger as
(
select

    -- specific conditions here
    case 
    when DATEPART(hour,arrived) between 0 and 7 then 
       'First Shift' 
    when DATEPART(hour,arrived) between 8 and 15 then
       'Second Shift' 
    when DATEPART(hour,arrived) between 16 and 23 then
       'Third Shift'         
    else
       'Hurry, inform the programmer of the anomaly!'
    end 
       as segment,

    *

    from attendance
)
insert into yourtable(segment, total, the_max)
select segment, count(*), max(arrived)
from tagger
group by segment;



select * from yourtable