Question

I need help to create a query in sql 2005.

I have 4 dates: 1 standard startdate and 3 date to compare.
I need to count the datediffs in days in ranges of 10.

datediff(day, startdate, enddate1)

How many times the range from 1 till 10, from 11 till 20 and from 21 till 30 will appear.

This for every 3 enddates!

Then a sum of all (3 enddates) 1 till 10 aso ( 510 times < 11, 275 times > 10 and < 21)

After this calculating the percentage of the ranges by all enddates.

Like 510/785 = XX.XX% and 275/785 = XX.XX%

Does I make myself clear?

Thanks in advance
1SeoAdvies

@mitch-wheat, It’s not a poor question it’s a difficult question to explain!
There is no table to explain this. Nearly Every table has a datatimefield!

I will try it again to explain this in very simple english.
I have a table with a datetime field. In a excelsheet I have an other datetime.
Both have the same key.
I know how to calculate the datediff in days.
I want to know how many time the datediff between 1 and 10 will appear.

example:

datediff(day, DateTime1, DateTime2) = 2

datediff(day, DateTime1, DateTime2) = 3

datediff(day, DateTime1, DateTime2) = 11

datediff(day, DateTime1, DateTime2) = 2

datediff(day, DateTime1, DateTime2) = 3

datediff(day, DateTime1, DateTime2) = 11

datediff(day, DateTime1, DateTime2) = 7

datediff(day, DateTime1, DateTime2) = 6

The result is

    < 11  = ***6*** (smaller then 11)

10 and <21 = 2 (between 10 and 21)

Sum the results 6 + 2 = 8

Calculate percentage:

smaller then 11 = 6\8 = 75%

Greater then 11 + <21 = 2\8 = 25%

The bold /invers items are the values I need!

Does I make myself now clear????????

Thanks in advance

Answer 1

SQL Fiddle

MS SQL Server 2008 Schema Setup:

create table YourTable
(
  dt1 datetime,
  dt2 datetime
)

insert into YourTable values(getdate(), dateadd(day, 2, getdate()))
insert into YourTable values(getdate(), dateadd(day, 3, getdate()))
insert into YourTable values(getdate(), dateadd(day, 11, getdate()))
insert into YourTable values(getdate(), dateadd(day, 2, getdate()))
insert into YourTable values(getdate(), dateadd(day, 3, getdate()))
insert into YourTable values(getdate(), dateadd(day, 11, getdate()))
insert into YourTable values(getdate(), dateadd(day, 7, getdate()))
insert into YourTable values(getdate(), dateadd(day, 6, getdate()))

Query 1:

select S1 / S2 as 'smaller than 11',
       (S2 - S1) / S2 as 'greater than 11 + < 21'
from (
     select 1.0 * sum(case when datediff(day, dt1, dt2) < 11 then 1 else 0 end) as S1,
            1.0 * sum(case when datediff(day, dt1, dt2) < 21 then 1 else 0 end) as S2
     from YourTable
     where datediff(day, dt1, dt2) < 21
     ) as T

Results:

| SMALLER THAN 11 | GREATER THAN 11 + < 21 |
--------------------------------------------
|            0.75 |                   0.25 |